A CONTRIBUTION TO THE GEOLOGICAL HISTORY OF SUFFOLK Part 5 THE EARLY PLEISTOCENE The Crag Epochs and their Mammals H A R O L D E . P . S P E N C E R , F.G.S.
can be few geological formations with a larger or older literature than the Crag Sands of Suffolk of which by far the greater part is devoted to the vast accumulation of molluscan fossils. In the 1890 Geological Survey Memoir by Clement Reid there are no less than twenty pages of references in the Bibliography, also on pages 6 to 9 and from 71 to 82 there is a summary of the various conclusions of a number of authorities, the references dating from 1659 to 1877 and naturally other papers appeared in subsequent years. At this time there was a universal misapprehension that all the Crag deposits belonged to the Pliocene and the major break between the Coralline Crag and the Red and Norwich Crags was not recognised. This erroneous view was mainly based on the percentage of extinct and living mollusca and the belief that the mastodont teeth were indigenous to all the Crag beds was so deeply rooted that all evidence to the contrary was either ignored or an attempt made to explain it away. THERE
Early in the present Century some authorities began to recognise that there is a break between the two lower Crag deposits and that from the Red Crag to the Cromerian Forest Bed Series was rightly the early part of the Pleistocene. This eventually led to a revision of the Plio-Pleistocene Boundary at the 1948 International Geological Congress in London when various proposals by different specialists were made, some of which would have drawn the boundary through the middle of the Red Crag where no logical, or recognisable, division can be made. The late Professor P. G. H. Boswell, who in his lifetime was perhaps the highest authority on the Crags, when faced with these conflicting proposals pointed out that the only possible British boundary was at the base of the Red Crag. It is curious that at no time during the controversy was any consideration given to the very significant evidence regarding the presence of true elephant and horse remains in or below the Red Crag, nor the presence of various species of deer belonging to the continental Villafranchian fauna. Professor J. S. Henslow drew attention to the indigenous mammalian fossils in the Red Crag, not below in the Basement Bed, as early as 1847 at an early meeting of the British Association at Ipswich, by pointing out their less mineralised condition, and in one of the Memoirs of the Geological Survey mention was again made of the two classes of mammalian fossils, one heavily mineralised the
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other less so and often "friable"; none of these, however, were described as such and very few seem to have been collected. One of the earliest accounts of the Crag is a letter by S. Dale describing Harwich Cliff and its shells, dated 1704; due to attacks by the sea this site vanished long ago. T h e Reverend H. Pickering wrote in 1745 about "manuring the land with fossil shells"; presumably the value was in the calcium carbonate of their composition since great quantities of Chalk are similarly used at the present time. This is said to have been due to the accidental spillage of a load of shelly Crag on a field after which it was observed that the com grew better on that spot. Latterly an attempt to commercialise the Red Crag was made at Levington by sifting and bagging comminuted shell fragments as grit for chickens. That attention was given to the Basement Bed of the Red Crag, which was also known as the Nodule Bed, Detritus Bed, and the SufFolk Bone Bed, is shown by the account given by the Reverend Professor J. S. Henslow in 1844, of the phosphatic nodules, " C o p rolites" (fossil dung), which occurred in the basal bed in considerable numbers. He remarked on their association with the "Cetotolites", i.e., petro-tympanics (ear bones) of Cetacea, and quoted John Brown of Stanway, who found that they contained phosphate of calcium in a similar proportion to the nodules in the London Clay and, from their association with the fossils of small Eocene crustaceans in the Basement Bed, concluded they were derived from that formation. Consquent on this revelation numerous pits were opened in the Red Crag for the new fertiliser industry at Ipswich and Stowmarket and probably had something to do with the canalisation of the River Gipping between those two towns. At that time clergymen, doctors, retired army officers, and other persons of means, and with a hobby of collecting curiosities took advantage of the opportunity to acquire shells and other fossils f r o m the Crag for their cabinets. Indeed there are people today who cannot refrain from picking up these fossils in places where the Red Crag is exposed and the shells occur in profusion. Fossil bones and teeth occurred sparingly with the coprolites and of these the greatest prizes were the teeth of mastodons which had acquired a glossy patina due to the friction of sand in moving water. In the heyday of collecting some of the most perfect of the large third molars changed hands at sums from ÂŁ6 to ÂŁ20. Large collections of fossils from the Crag were eventually sold for as much as ÂŁ200 and then split up into smaller series and re-sold for proportionate sums. T h e acceptance of the mastodon remains as of Pliocene age no doubt contributed to a large extent to the confusion regarding the true age of the Red Crag.
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RED CRAG BASEMENT BED The Coprolites With every problem there are those who for one reason or another hold opposite opinions and it was thus with the coprolites, or phosphatic nodules in which from "44% to 56% of phosphates was determined by analysis, with 20% to 25% of calcium and magnesium carbonates, the phosphatic matter being equivalent to tribasic phosphate of lime (bone earth)". Sir E. Ray Lankester (author of "Science from an Easy Chair") was one who regarded the phosphatic nodules as rolled lumps formed on a shore where there were large quantities of bones from which the phosphatic matter was absorbed. This is in the highest degree improbable if only for the reason that there is not one scrap of evidence to show that such numbers of bones ever existed. The true facts are that such phosphatic nodules do occur in the London Clay, of which John Brown of Stanway was well aware from his observations of that Clay in Essex. In Suffolk a great part of the London Clay was destroyed, largely by the incursion of the Red Crag Sea; indeed there are places where it is entirely missing and the Crag sands lie on the Reading Beds. T h e nodules were derived from this clay. True coprolites are invariably the droppings of carnivorous animals and the form of many of the nodules is clearly proof of their origin. For instance, there are in collections rather curious cork-screw-like objects which are the coprolites of sharks and some are either of very small species or from very young specimens. Somewhat similar objects in Ipswich Museum are actually coprolites of Jurassic ichthyosaurs which are most likely to have been transported to Suffolk by ice. One other specimen, also at Ipswich, is an obvious coprolite, and according to the size and form this could have been the sign of a passing dog: it is most unlikely to belong to any marine animal. This specimen is recorded because the implications are that it must have been deposited in a very dry terrain, perhaps in desert conditions, since in a rainy climate it could not have been preserved. The preservation of coprolites of carnivores is due to their high mineral content of calcium and magnesium phosphates whereas it is only in desert conditions that the droppings of herbivores are likely to survive; in such places they are often the main source of fuel in modern times. Some curious specimens in the Ipswich Museum do not appear to have received previous notice. They vary in size but all are small and the only possible explanation of their origin is that they are coprolites of an exceptional kind, i.e., casts of the intestines of the various animals represented, which were presumably marine.
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Most collections of objects from the Crag have two or more shark vertebrae embedded in phosphatic matter, probably coprolite, and similar items have been found in London Clay. Other Eocene vertebrate remains include mandibles or parts of skulls of the tiny ancestor of the horse famiiy (Hyracotherium) embedded in simiiar phosphatic matter, implying that these animals were preyed on by some Eocene predator at present unknown. Another form of phosphatisation has been recognised in recent years when there has been an opportunity to examine a series of elephant teeth, etc., which had been trawled from the North Sea floor, all from an unknown locality except for one labelled " T h e Channel". They were collected from fishermen by a Dr. Bree of Colchester and the specimens are preserved in the Natural History M u s e u m of that town. T h e species are Palaeoloxodon antiquus and Mammutbus primigenius and although they are all to some extent encrusted with phosphatic matter they are not of Crag age. T h e y presumably date from the penultimate and ultimate interglacials, the latest being perhaps 25,000 years old. T h e interesting fact is that being so encrusted they resemble to some extent fossils from the Basement Bed of the Red Crag, for which no reasonable explanation for their fossil condition has been expounded. It now appears that the probability is that bones or teeth of mammals lying on the sea bed, under unknown conditions, may become phosphatised with comparative rapidity geologically speaking. T h e r e are some more elephant teeth in Ipswich M u s e u m from the same source of which all record had been lost. For many years they had provided food for thought but now the problem seems to have been solved. DĂźring the past half Century a number of bones of various periods from the North Sea floor have been examined but none have been in the phosphatised condition described.
A pre-Red Crag Ice Age When the subject of a pre-Crag glaciation was mentioned to the late Professor P. G. H . Boswell he had but one reply "But there is no Till", this implies a lack of inclination to examine the evidence and there are facts which may be instanced in reply to such a remark. For one example it may be demonstrated there is no London Clay below Red Crag, similarly it has been claimed there is no Gipping Till eastward of a line from Ipswich northward but it can be demonstrated that there is, notably at Chillesford and Oulton, Lowestoft. T h e presence of far travelled rocks and fossils from sources to the north were explained by Boswell as having been transported by floating ice but apparently he omitted to take into consideration that the molluscan fauna indicates a climate possibly as warm as the present Mediterranean region. Many stones in the Red Crag
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Basal Bed are scratched or striated in a similar manner to those found in glaciers and glacial boulder clays, or tills, These he attributed to the movement of floating ice grounding on the shore and movement due to the tides; an untenable theory since the evidence is against the possibility of ice being able to float so far south at the period in question. In fact the presence of this iceborne and scratched or striated material is best explained by its having been derived from an earlier glaciation. There is, however, stronger evidence for a pre-Crag glaciation in the presence of blue and white "basket-patinated" flints below the Crag sands. These flints commonly occur in chalky tills and their peculiar condition is due to a thin film of white having formed over the black fractured surfaces of the flint. On the facets there are usually a number of criss-crossed white lines, these are due to the movements in the ice which causes stones to grind one against another and Scratch the flat surfaces where the agencies which cause surface changes on the exterior of flints are able to penetrate deeper, producing the white lines. Had there been no glaciation during the interval between the retreat of the Coralline Crag Sea and the formation of the Red Crag Basement Bed there could be no basket-patinated flints therein.
Basement Bed and sub-Crag Faunas The far travelled erratic rocks and fossils recorded from the Red Crag Basement Bed include:— Sundry igneous rocks—vein quartz, etc. Chert' Jurassic fragmentary ammonites and belemnites An Ichthyosaur vertebra and coprolites, reptile teeth, Kellaway Rock with RhynchoneUa socialis from Yorkshire. Cretaceous Lower Cretaceous rock with ammonite, etc., from Yorkshire. Belemnites minimus from ?Lincolnshire Red Chalk.
Locally derived material includes:— Eocene
L o n d o n Clay Septaria. Limonitic concretions resulting f r o m the oxidation of London Clay iron sulphide nodules. Fossil wood, various species ex London Clav. Coryphodon teeth. Lophiodon teeth. Hyracotherium, parts of jaws with teeth in phosphate. Reptilia, Crocodile scutes, portions of turtle carapace. Pisces, Pristis cf pectinatus rostral teeth, generally confused with worn shark teeth. Cylindracanthus rectus, short longitudinally grooved fragments of the hollow rapier-like rostral process, the hollow is double near the base. ? Lepisosteus sp. rhomboid Ganoid scales. Acipenser (sturgeon) dermal scutes and bony plates from the skull.
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Teeth, etc., of other species represent:— Aetobalis, Elasmodus, Edaphodon, Chrysophrys, Myliobalis, Phyllodus, Pycnodus, Halicopsis spp.—heads and fore portions of bodies phosphatised, similar to specimens found in London Clay. Cetacea, Zeuglodon teeth. Crustacea—Lobster-type:— Hoploparia belli, Hoploparia sp., H. gammaroides, Thenops scyllariformis, T. koenigii, Archaeocarabus bowerbanki. Crab-type:— Dromlites bucklandi, D. leachi, Zanthopsis unispinosa, Z. bisipinosa, Z. leachi, Zantholithes bowerbanki, Cyclocorystes pulchellus. Miocene—derivation mainly from marine deposits. Mastodon anguslidens, portions of teeth via Coralline Crag. Halitherium canhami, part of skull, Ipswich Museum. T e e t h in Yorkshire M u s e u m , York. Hoplocetus crassidens, teeth, also in Boxstone. Mesoplodon sp. portion of mandible with sandstone (FIG. 27A).
Eucetus amblydon, tooth with sandstone. Undetermined Cetacea—Tympanic in Boxstone. Bone in Boxstone. Numerous glossy mineralised bones and pieces of ribs similar to specimens from Lower Miocene beds in Australia. Pig, Sus palaeochoerus, various teeth, metatarsals. Mollusca, the Boxstone fauna is too lengthy for inclusion here. Pliocene—the derivation probably due to both marine and glacial action. Mastodon (Anancus) arvernensis, teeth and portions of same. M. borsoni, portions of teeth. M. longirostris, portions of teeth. Axis pardinensis, antler bases, teeth, and some bones. Cervus suttonensis, antler bases, teeth, and some bones. Sus spp. teeth. Cetacea various species:— teeth, petro-tvmpanics, bones. Phoca spp.? bones. Trichechus huxleyi, canine teeth (tusks). Possibly older? T h e Earlier Pleistocene—derivation due to both glacial and marine action. Elephant, Archidiskodon meridionalis, tooth. Equus robustus and sp. teeth and bone. Gazella anglica, horn cores, teeth, bones. L o c a l l y d e r i v e d e r r a t i c s i n c l u d e C h a l k flints, f r e s h l o o k i n g a n d unrolled with slender projections u n b r o k e n while o t h e r large blocks of flint w i t h h o l l o w s o c c u r , r e t a i n i n g a l a r g e s a m p l e of t h e o r i g i n a l matrix. S i m i l a r flints h a v e b e e n f r e q u e n t l y o b s e r v e d in L o w e s t o f t Till. L a r g e n u m b e r s of t h e w e l l - r o u n d e d s l a t e - c o l o u r e d flints o r i g i n a l l y d e r i v e d f r o m t h e d e s t r u c t i o n of t h e O l d h a v e n B e d a n d f o r m i n g t h e B a s e m e n t B e d of t h e L o n d o n C l a y o c c u r a n d a r e v e r y c o m m o n a t B r a m f o r d w h e r e all t h e L o n d o n C l a y h a s v a n i s h e d . S o m e e r o d e d - l o o k i n g o d d l y s h a p e d flints d o o c c u r f r o m t h e Bullhead Bed below the T h a n e t Bed w h e r e they are a dark greenish c o l o u r a n d h a v e a c q u i r e d a r u s t y a s p e c t . T h e b u l k of t h e s u b C r a g flints b y r e a s o n of t h e i r d e e p b r o w n p a t i n a a n d b a t t e r e d appearance m u s t have h a d a varied history before being incorp o r a t e d in t h e C r a g b a s a l b e d , t h o s e w h i c h a r e s t r i a t e d a r e o b v i o u s l y i n d i c a t i v e of a g l a c i a t i o n a n d it is n o t b e y o n d t h e b o u n d s
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of possibility that they suffered in more than one cold period. Flints with thermal fractures are very common and a number of these were included in the rostro-carinates once thought to be primitive artifacts made by an early ancestor of mankind. Man and the Red Crag Here it will be convenient briefly to record something of the somewhat bitter controversy which arose from the work of J. Reid Moir who succeeded Sir E. Ray Lankester as President of the Ipswich Museums. An important fact to bear in mind is that during the period in question the accepted view was that the Crag was of Pliocene age and it was unthinkable that man had any ancestors so far back in geological time; we now know from the results of Dr. L. S. B. Leaky's work in East Africa that the age of man is much greater than was once thought possible. Moir, inspired by the discovery of a human mandible in 1855 in the Red Crag at Foxhall Hall three miles from the centre of Ipswich, devoted many years to investigations in search of further evidence as proof of the co-existence of man and the Crag. The writer was introduced to Moir in 1920 and was instructed in the nature of the characteristics by which flint and other stone artifacts were acceptable as the work of man, and in the nature and cause of thermal fractures and frost pitting which sometimes produced forms somewhat resembling artifacts. With regret it must be recorded that in later years Moir and his great friend Ray Lankester turned a blind eye to the latter type of fracture and thereby did great harm to their cause. During the twenty odd years of association with Moir it was not possible to venture any contrary opinion. Moir was able to get funds and employ a man who was trained as his excavator and the base of the Red Crag was investigated at a number of sites no longer available of which an important one was the Dales Road Brickfield (Bolton's). A number of artifact-like flints were found here in the Basement Bed which, if taken from a younger Stratum would have been acceptable, but any excuse to disparage Moir's claims was used by his opponents. Here it was the fact that Gipping glaciers had disturbed the bedding and the flints had been fractured by that event. That this view was unfounded is proved by two facts; one, all the "artifacts" had the fractured surfaces deeply patinated and stained brown and secondly, slender projections about the diameter of a pencil on entire flint nodules were intact. If these had survived the pressure of untold tons of ice it is extremely unlikely that larger flints could have been fractured. This is one of the places where flints with the blue and white Basket patina were found in the Basement Bed with brown iron-staining like most of the other flints.
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Coe's Chalk Pit at Bramford was another site of importance in which one large flake resembling those of the pre-Acheulean Clactonian industry was discovered but not with the typical flaking angle. If it were placed with the Clactonian artifacts from a later deposit it would not be questioned. The most remarkable discovery here was made by the Abbe Brueil. It is preserved in Ipswich Museum and is a brown pebble longitudinally scored with parallel lines of such a character that they can only have been produced by scraping with the edge of a sharp flint, no other similar specimen has been noticed. In size and shape it resembles the steatite sling "bullets" made and used by the natives of New Caledonia in the Pacific. The term "rostro-carinate" was coined by Lankester for largish flints with a beak-like profile, resembling the prow of a boat. While there are a few which appear to owe the shape to deliberate flaking and seem to be a development of two notches made in a flint to produce a point, the greater number are the result of accidental fractures combined with thermal "pot-lid" fractures. An opportunity to examine the bulk of Moir's Crag and Cromerian Forest Bed flints came during 1954 when they were removed from the Ipswich Museum basement to a new storage. Seemingly all the stones taken from the basal bed of the Red Crag by Baxter, Moir's excavator, had been preserved and a large number had no claim to interest of any kind. A proportion of the remainder were in the same category as the rostro-carinates and others with mechanical fractures which could possibly have been artificial were not in any way adaptable for use as a tool. Finally there was a residue of flakes, etc., which would pass in any assemblage of Upper Pleistocene artifacts. It is one of the odd tricks of fate that after Moir's death in 1942 evidence of a true Clactoniantype industry became known as a result of the erosion of Bawdsey Cliff, albeit not from the Basement Bed but from the Red Crag Sands above: it is unfortunate that none of the specimens were found in situ, so it has not been possible to determine if they were from one particular level. These flakes and cores all have a creamy patina with slight iron-staining and iron impregnated clay is in hollows of some of the flints. The creamy patina implies that the flints were exposed to weathering until a white patina had time to develop and after being incorporated in the Crag a slight yellowish tinge was acquired. This type of patina is found on many flints found within the Crag sands and has been noted on possible artifacts from Foxhall and Beggar's Hollow, Ipswich. Foxhall Man The story of the fossil which became known as the "Foxhall Jaw" was summarised in the April number of the East Anglian
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Magazine, 1965. It was unearthed in 1855 from a pit on the farm of Mr. Laws, now Foxhall Hall, and sold to John Taylor, a druggist, at 97 Fore Street, Ipswich, by a workman for 2/6d. "beer money"*. Sir Thos. Beaver became interested in the fossil when paying a visit to his son who was then living at Taylor's house and he acquired it only five weeks after its discovery. In 1857 it passed to an American, Dr. R. H. Collyer, who took it to Professor Quekett at the Royal College of Surgeons where it was shown to Sir Richard Owen who retained it for two years without comment. Düring 1859 it was examined by Joseph Prestwich but there is no record of any opinion he may have expressed. Following the publication of Lyell's "Antiquity of Man" Professor Huxley learned of the mandible and became interested. The specimen was exhibited at a lecture on Primitive Races given to the Ethnological Society by a Mr. Crawford through the agency of Sir E. Belcher, as a result of this it was discussed by Busk, Lyell and Murchison, who were eminent authorities of the period. Busk expressed the view that it must be the "jaw of some old Roman woman", a view he later retracted when next day Huxley and Taylor visited him. Huxley then expressed the view that it was a "most extraordinary specimen which exhibited some peculiar features which did not seem to indicate an extinct or aberrant race", but it was considered that it was not in the fossil condition in which a Crag bone was expected to be. This view was typical of the conditioned thought of geologists at that time because the mammalian fauna coeval with the deposition of the Crag Sands was not recognised. Professor Busk and Dr. Hugh Falconer took the "Foxhall Jaw" to Paris in 1863 and a Statement was published in July ofthat year. "The specimen is a very remarkable lower jaw of a human subject now belonging to Dr. Robert H. Collyer. It is reputed to have been in the gravel heap of a Coprolite Pit near Ipswich. Although retaining a portion of its gelatine (?) it is infiltrated through and through with iron, the Haversian cords are filled with red oxide and a section of the fang is partly filled with the same metal. The specimen proves that the human jaw if favourably placed is equally susceptible of impregnation with metallic matter as the bones of any other animal:— Signed E. BUSK, H. FALCONER." Busk, however, thought it could have no relationship to the age of the fossils in the Coprolite Bed. (This in fact is perfectly true since its fossil condition is precisely like that of the other indigenous mammals.) It was regarded as of some antiquity and remarkable for the amount of iron therein. Collyer subsequently returned to America and is believed to have taken the •Beer at that period was about one penny a pint and f a r m workers were given malt at harvest time for the making of home-brewed beer. It is believed that this practice continued at least u p to the first world war.
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mandible with him but efforts to discover what happened to the fossil have been fruitless. It must be emphasised that the Foxhall mandible did not come from the Red Crag Basement Bed, if it had it would be older than the Crag and would have presented a greater problem regarding its age. There is good reason to believe that it probably came from what Moir called the sixteen foot level in the Foxhall Hall pit where a secondary lenticle of coprolites and partly decayed fragments of sub-Crag bones was discovered during his investigation. In this bed some fire-marked flints were discovered, other flints with Crag staining and crackled in the same manner as cooking stones from later prehistoric hearths, were taken from the lower part of the Red Crag at Piper's Vale, Ipswich. It would appear that the bed at the sixteen foot level was exposed to weathering conditions for some time during which the heavily mineralised sub-Crag fragments of cetacean rib became splintery and friable. There can be little doubt that any early men living near the coast would seek mollusca or other sea food with the possibility of being trapped by a rising tide and that such an occurrence could account for the jawbone. In Africa early hominid remains date from about two million years for the Early Pleistocene, to which age the Pleistocene Crag series belongs. Implied pre-PIeistocene Geological succession The Red Crag Basement Bed may be likened to the remains of a series of volumes of geological history of which some are lost and only portions of others are preserved. Elsewhere in England
Portion of mandible near the Symphysis of Mesoplodon sp. with encrusting sandstone of the same type as the Boxstones of Miocene origin from the Red Crag Basement Bed.
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FIG. 2 7 B
T o o t h of Carcharodon megalodon embedded in sandstone. An indication ot the relationship of this species with the Boxstone molluscan fauna British M u s e u m (Natural History).
the Eocene sands and clays of shallow seas were succeeded by lakes and lagoons with a stränge and varied mammalian fauna. T h e deposits of this stage were followed by Oligocene deposition of fluvio-marine fresh and brackish water beds and a similar mammalian fauna on land. Dßring the Miocene earth movements occurred in southern Britain which have been described as the outer ripples of the Alpine storm, during which the Alps are believed to have formed. There are no known surviving deposits of the age but that there were some deposits is proved by the denved fossils below the Pliocene Coralline Crag and the Early Pleistocene Red Crag in their respective basal deposits, they are indicative of both terrestial and marine deposits. There is little surviving evidence of the earlier Pliocene terrestial stage apart from the very few mammalian remains from Doveholes, Derbyshire
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which are in the Manchester Museum. All that survives in East Anglia are the three remnants of the Coralline Crag in South-East Suffolk. It may be seen frorn the list of faunas given that both land and marine animals are represented which is clear evidence of the former existence of lake and river deposits succeeded by marine beds in most epochs. This is more clearly shown by what can be inferred from our Pliocene beds in which there are now few exposures and the Basement Bed has not been seen for about a Century, when an account of the "Crag Beds of Suffolk and Norfolk" was published by Joseph Prestwich in the Quarterly Journal of the Geological Society for 1871, Vol. XXVII, pp. 115, 325, and 452. He states that the pit opened in the Sutton Knoll was not productive and was levelled after it had been in Operation a short time, also that Ray Lankester was the only other geologist to see the Basement Bed below the Coralline Crag. Unfortunately his list of vertebrate fossils is limited to the more important items, however, the Boxstones are mentioned together with "worn blocks" of London Clay Septaria and numerous phosphatic nodules. None of the blocks were angular or striated but a very large boulder of "dark-red porphry" of about a quarter-ton weight seems to have been lying on the surface of the London Clay below the Coralline Crag, a fact most difficult of explanation. It would be most interesting if this remarkable erratic could once again be disinterred, it should be possible to discover its origin. From this record it is to be presumed that there was no glaciation preceding the formation of this basal bed of about one foot in thickness. It has been proved in this record that the Boxstones are older than the Coralline Crag together with the mastodon teeth, and those of Carcharodon megalodon and other sharks (FIG. 27B). In the same bed were teeth of Rhinoceros schleiermacheri and deer, either Axis pardinensis or Cervus suttonensis, perhaps both, one of the best specimens of a shed antler base of the latter species from this site is in the British Museum (Natural History), it is partly encrusted with small Baianus, similar specimens from below the Red Crag are nearly all much worn due to beach rolling. The Mastodons It is known from records of Pliocene faunas in European deposits that three of the four known species of mastodon belong to that epoch, the fourth belongs to the earlier Miocene epoch and is less well represented by fossil teeth in the Red Crag Basement Bed. A significant fact is that teeth, which are the final element of a mammalian skeleton to survive the various destructive forces of nature, are the only evidence of mastodons in this country and the only specimen known from an English deposit, apart from those below the Red Crag, or in the Norwich Crag and
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Westleton Beds (sensu stricto), is from the Doveholes already mentioned. No bones have been observed in any Crag collection examined which could possibly be referred to any species of mastodon, there are, however, a number of thoroughly mineralised portions of ivory tusks, the fossil condition of which differing considerably from elephant ivory in the Crags, must indubitably belong to the older genera. Portions of two smallish lower third molars of Mastodon angustidens and a few other pieces in the Ipswich collection were first recognised by Dr. Miklos Kretzoi, an Hungarian specialist in vertebrate palaeontology, during a visit to this country as a guest of the British Council in 1965. They had been overlooked partly because they differ only slightly from teeth of M. longirostris and to the fact that although Sir Richard Owen had mentioned Mastodon angustidens in 1846, in his "History of British Fossil Mammals and Birds", his illustrations were of M. arvernensis. Thus lt is only recently that Tetrabelodon (Trilophodon) angustidens can rehably be included in the sub-Crag fauna. The teeth of this species have comparatively clear V a l l e y s between the ridges with rudimentary mammilae near the middle of each ridge base. It is of interest that traces of Coralline Crag remain below the crown in one of the Ipswich specimens and another has the root fang complete. Of greater importance is the specimen in the Reed Collection of the Yorkshire Museum in which the Valleys were originally filled with the same hard sandstone of which the Boxstones are composed, this has been removed but fortunately small patches remain on the underside. Plaster casts of the tooth in its original condition are in sundry collections and new ones with the Valleys clear have been made. It was Sir E. R. Lankester who first described the tooth, but other authorities disagreed in as much as they were not able to accept it as a complete tooth of three ridges, i.e., a second molar, in fact the objectors appear to have been correct as it is apparently an upper third molar lacking the posterior ridges. These teeth could not have occurred below the Coralline Crag had there not been in an earlier Miocene age a terrestial stage between two marine phases. Lankester's tooth with its sandstone is indicative of the land on which this mastodon lived having been destroyed by a marine incursion, just as a similar incursion is indicated by fossils of land animals of the subsequent early Pliocene and early Pleistocene terrestial stages and proved by the presence of those faunas in the basal deposits below the Coralline and Red Crags respectively. The three Pliocene mastodons are, according to Karl von Zitters "Palaeontology", Tetrabelodon (Tetralophodon) longirostris, Mastodon borsoni, and M. (Anancus) arvernensis. T. longirostris is a Lower Pliocene species but it is curious that these generally incomplete teeth are in a better S t a t e of preservation than those of
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M. borsoni, which like Anancus arvernensis ranged from the Middle to the Upper Pliocene. Fairfield Osborne, an American specialist whose monumental work on the "Proboscidea" was world-wide in its scope and dealt with an extraordinary number of evolutionary adaptations to a number of varied environments within the family of Mastodonta, thought the mastodon teeth from the Suffolk Crags showed some distinctive features and proposed the name A. falconeri for them, however, there is an Indian mastodon, M. falconeri Lydekker, which could make for confusion. It is proposed to continue to use the name A. arvernensis of Croizet & Joubert. Of the latter species the greater number of nearly entire and entire crowns of teeth have survived but as is general with mastodon teeth the root fangs have been lost at a variety of times in their history as fossils, only in a few are they partly preserved. In the Villafranchian of Italy this species overlapped into the lower stage of that formation and was coeval with the early elephant Archidiskodon meridionalis, but there is no evidence of this in the Red Crag. In Norfolk, however, there is a record of remains of both species occurring together on what was thought to be an old land surface, which if true could well be a relic of the pre-Crag terrestial stage of the Early Pleistocene. The Tetrabelodonts all had four tusks, which are in fact greatly developed incisor teeth, and it is perhaps somewhat surprising that more portions of tusks have not been recorded from the Crag Basement Beds. The fact is that most specimens in collections are from the Norwich Crag, notably from the Easton Bavents Cliff near Southwold in mid-East Suffolk and have been taken from the Westleton Beds of the Blyth Valley in recent years since the deposits were exploited for aggregate for concrete manufacture. The fact that sporadically distributed teeth of A. arvernensis occur in both Norfolk and Suffolk Norwich Crag is extremely difficult to explain. (No such teeth have been recorded from the Stone Bed below the Norwich Crag which is principally a packed mass of flints in places where very few have not at least one, and often two or more mechanical flake scarj, with some having some resemblance to humanly fashioned "cores" but so far as is known no flakes or flake implements have been found in association at these inland sections. Clacton-type flake tools have, however, been found in the Weybourne Crag of the Norfolk coast and it is considered that the similar artifacts said to have come from the Forest Beds are mainly derived from that horizon.) No fewer than 137 Arvernensis teeth, or fragments thereof, from animals of various ages have been traced and there is little or nothing by which it can be distinguished whether they were from Red or Norwich Crag: there are a few specimens labelled as from Norfolk which, without data, one would have expected to have been taken from the Suffolk Red Crag basal bed.
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T h e Norwich Crag is generally regarded as a younger member of the Crag Series but there is no known section where the two Crags occur together one above the other. Recent evidence has led to a suspicion that the grey-coloured Crag in the lower part of bores made at Sizewell may possibly be Red and not Norwich Crag. T h e Coralline Crag extends as far to the north as Sizewell as an offshore outcrop and during the earlier marine phase of the Early Pleistocene a great quantity of this Pliocene deposit must have been destroyed. T h e r e can be little doubt that numbers of the sub-Crag fossils would have been liberated and normally included in the basal bed of the new formation, which in the area in question is well over a hundred feet below the present sea level, thus there is no clue to indicate if this did occur. What is known, however, is that the Norwich Crag mastodon teeth, all of one species, occur sporadically all over the accessible Norwich Crag but are not recorded from the Weybourne Crag. If the teeth were derived from the former northward extension of the Coralline Crag why are there no other fossil mammalian remains such as the Pliocene deer Axis pardinensis or Cervus suttonensis or the polyzoa and more robust mollusca which are abundant in the Red Crag adjacent to Coralline Crag outcrops? Only one tooth of A. arvernensis is known to have been brought up from the sea bed of Sole Bay off Southwold, it is in Ipswich M u s e u m ; in view ot the number of Norwich Crag elephant bones from this source perhaps more might have been expected. T h e tooth, a first molar, is unique in having the root fangs more or less complete as though they had been protected by the bone of the jaw which had not been mineralised, another unusual feature is that this fossil is not mineralised in the same way as all the other mastodon teeth; the crown of this tooth is black. Another unique specimen is in the Norwich Castle Museum. It is a maxillary of a very young mastodon with a pre-molar and in the alveolus of another tooth are some of the root fangs. T h e fossil condition resembles some bones from Red Crag but it is recorded as having been discovered on the beach at Sizewell over four miles north of the nearest Red Crag. T h e broken edges of bone are rather jagged and the specimen has not been subjected to beach rolling as would have been expected. T h e Sizewell Crag is essentially sand and as far as excavations for the Atomic Station have exposed it the only fossils were fragmentary shells. The foregoing facts are some of the unsolved problems of the Crags and by no means the least. T h e removal of fossil bones by holiday visitors to the coast without having them recorded is a handicap to investigation, only rarely did anyone bring specimens to the Ipswich Museum for determination and only on one occasion was a parcel of finds sent for naming—by a school party from Yorkshire. These had to be returned for the school museum
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where their future preservation is questionable, as experience has too often shown. Teeth of Crag horses are uncommon but a drawing of a good specimen from Easton Bavents Cliff was made owing to the finder taking it to the Museum.
Crag Horses There are at least two kinds of horses represented in the Red Crag. One, a large species, was originally referred to Equus stenonis but Dr. A. Tindell Hopwood of the British Museum (Natural History) was of the opinion that this species was not present in the British Isles and that the teeth belonged to Equus robustus, syn. magnus. A smaller species is represented by a tooth in Ipswich Museum which is partly encrusted with phosphatic matter, it is indistinguishable from a similar tooth of a recent horse. In the Basement Bed, horses are represented by a thoroughly mineralised tooth of the former species from Bawdsey Cliff in the British Museum (Natural History). From Felixstowe the distal end of a metacarpal was obtained and is now at Ipswich. Other sub-Crag equine fossils are believed to exist but they have not been traced. Teeth of horses are better represented in the Red Crag where they are still rare, however, coastal erosion and excavations in the Norwich Crag and the Westleton Beds prove their continued survival into the Cromerian Forest Bed Series. Like the elephants the true horses undoubtedly developed during the earlier Pleistocene terrestial stage of which the deposits were destroyed by a glaciation and the marine incursion of the Red Crag Sea.
The Red Crag Elephant It is unfortunate that the widely held erroneous opinion regarding its age rejected the idea of elephants in the Red Crag which may have affected the evidence now available. T h e only specimens now traceable are the sections of probably two pieces of a tooth, or teeth, discovered in the large pit behind the Churches at Trirnley, near Felixstowe. These were cut into slices and are now distributed among a number of institutions, the British Museum (Natural History), Birmingham University, Leeds Philosophical Museum, and the Yorkshire Museum. T h e Leeds sections were figured by Leith Adams as Elephas antiquus but from the thickness of the enamel of the plates it is clear they should be referred to Archidiskodon meridionalis. In the Palaeontological Memoirs of Dr. Hugh Falconer there are references to other elephant teeth from Red Crag which were in the collection of the Geological Society of London which is believed to have gone to the Geological Survey Museum, but they have not been traced there. T h e y were referred to the former species which is, from the present evidence, thought to be inaccurate. No mention is made as to whether these teeth were from the basal bed or from the
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Crag Sands but that the Crag Elephants were indigenous to the Crag is proved by a pair of lower molars from Falkenham. Lankester disputed that the elephant teeth could have come from the Red Crag and argued they must have been from the sand above the Crag. In this instance, had he gone to the site he would have found Crag up to the grass roots, but as usual the upper part of the Red Crag is decalcified and he seems not to have recognised this as part of the Crag formation. Only teeth, including a large portion of a tusk at Ipswich, are recorded from Red Crag but numerous bones as well as teeth of A. meridionalis have been obtained from both the Norwich Crag and the Westleton Beds of the Blyth Valley in recent years. There is a record of bones from Dunwich Cliff with other animal remains. Rhinoceros
Numerous teeth, chiefly mandibular cheek teeth, exist in various collections and there are a few more or less entire upper molars but these are generally represented by fragments. Some milk teeth are also known from the basal bed of the Red Crag. Skeletal remains of rhinoceros are of the greatest rarity, only two have been traced, one in an ulna which differs from the ulna of later Pleistocene species. It was dredged from the bed of the Orwell Estuary and is mineralised in the same way as the sub-Red Crag bones. The Crag occurs on the shores of the Orwell and at various times there has been a collapse of the end of high spurs which project into the Valley and were the cause of diversions in the course of the river. Fragmentary sub-Crag cetacean bones have been found on the foreshore of the Orwell at times during the past half Century and the ulna could well have been precipitated into the river as a result of one of the more remote landslides in the history of the development of the Valley. The only other bone is part of a nasal with the rugosity on which the "horn" was formed, nothing of its history is known but the presence of encrusting organisms is indicative of it having been dredged, though whether it is from the Orwell or from the North Seafloorcannot be decided. The above mentioned teeth have been attributed to Rhinoceros schleiermacheri and to R. incisivus. Latterly there has been various revisions of nomenclature and the former species is now put in the genus Ceratorhinus but by the time this paper is printed it may well have been changed again (this is one of the bugbears of palaeontology). R. incisivus is said to have been founded on Lower Miocene specimens that continued into the Middle Miocene, the upper molars are said to resemble those of Ceratorhinus schleiermacheri which can be confusing when dealing with imperfect specimens such as occur in the Crag. The latter species ranges apparently from the Middle Miocene to the Lower Pliocene and in attempting
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to differentiate between the species, the teeth of R. incisivus are invariably water worn and there is an external cingulum to the upper true molars and a more prominent inner cingulum on the pre-molars. If correctly determined the teeth of this species constitute further proof of former Miocene deposits in this part of the country. However, while Lydekker and Newton use Kaup's name for this hornless species R. insisivus apparently Cuvier's name Aceratherium incisivum has priority and is now in general use, this according to Zittel was a Lower Pliocene species which retained a degenerate fourth digit on the fore feet. T h e Ceratorhinus teeth are in a much better State of preservation when entire but to judge from the number of fragments in collections they seem to have been liable to break up easily, however, few of the specimens appear to have been beach rolled. T h e lower cheek teeth are much more common but it is more difficult to determine to which species they should be referred. In Ipswich Museum there are a few lower milk teeth probably of Ceratorhinus. Two upper molars of rhinoceros have been taken from Crag Sands, one is from Foxhall and the other, an M 3 , from Norwich Crag of Sizewell which has a curious history. For some unknown reason the two parts, it having been broken, became separated and one was exhibited with Upper Pleistocene rhinoceros teeth. When the Museum basement was cleared of accumulated material the major part of an upper third molar was found with a paper stating it came from Sizewell and the donor Mrs. Ogilvie. Sometime later the brown colour of the first portion was noticed and compared with the other because of the similar fossil condition when it was found that both were parts of the same tooth. It is probable that the pieces were separated in 1880 during the transfer from the old to the new Museum, they were reunited after about three-quarters of a Century. T h e rhinoceros family originated during the Eocene.
The sub-Crag Deer T h e two genera already referred to, Axis pardinensis and Cervus suttonensis constitute the only evidence of British Pliocene deer and their remains have been found only in the Basement Bed of the Red Crag, except for one antler base and two teeth from Sutton. T h e more common fossils, shed antler bases, are in general well mineralised but some appear to be less well able to withstand exposure to weathering when removed from the Crag. It was Professor Boyd Dawkins who described a number of Early Pleistocene deer as well as C. suttonensis. In his description of this species it is said to have a marked " w e b " in the angle formed by the beam and the brow tine, but it is curious that his figured types are of antler bases having the brow tine diverging from the beam at an angle of 80°. He failed to recognise the Axis-type antler bases as a different species, having a divergent
297 angle of about 45° and a very marked "web", but E. T. Newton figured a specimen in his Pliocene Vertebrata of Great Britain as Cervus dicranoceros which is apparently no longer a valid species. Dawkins also described some specimens as C. carnutorum but from thefigures,one is positively Euctenoceros falconeri and another probably a shed antler of an 'immature E. sedgwicki. The two latter are indigenous species from the Crag Sands above the basal bed. Owing to the fact that the name C. suttonensis became generally known and possibly because of the emphasis on the "web", in most collections this name is found on both species indiscriminately. The shed antler bases of the axis deer closely resemble the antlers of recent axis species of Asia. The antler bases with the narrower angle of the divergence of the brow tine most closely resembles the Upper Pliocene species, Axis pardinensis of Croizet and Joubert, which E. Heintz, in his recent work on the Villafranchian Cervidae of France and Spain, includes in the Villafranchian fauna. The fossils from the basal beds of the Coralline and Red Crags are clearly older and no antler remains of this Axis-type occur with the remains of other Villafranchian species, Euctenoceros sedgwicki, E. falconeri, and E. tetraceros in any part of the Early Pleistocene Crag Sands. The astragalus (ankle bone) is fairly common fossil from the basal bed but it is not possible to determine which of the Pliocene deer they belonged to, the majority are of a more or less uniform size but there are a few of varying larger sizes, while some which are smaller are thought to belong to Gazella anglica. A few other bones, all incomplete, are probably correctly classified as Cervus, they are portions of limb bones. It is not known if Dawkins saw the antler base of C. suttonensis from the Basement Bed of the Coralline Crag at Sutton, which is partly encrusted with Baianus, possibly B. crenatus, and which is mentioned by Prestwich, but it is not one of his co-types which are all from the base of the Red Crag. The former specimen is mainly grey in colour whereas thefiguredspecimens are all dark brown and with one exception markedly straight in the beam. One in the Yorkshire Museum has a slightly curved beam. The group of fossils in the Museum at Ipswich has an antler base less rolled than others but it is the other minor specimens which are the principal interest. In particular there is the base of a pricket from a young stag with a remarkably rugose burr and a broken pedicel, but sundry brow tines with variable sections having a tendency to nattening represent a character not found in other species or collections. These all have a black patina which is regarded as generally characteristic of this species, it being found in other specimens from various sites. The rolled brown fossils are thought to have lost the original patina during the period of beach rolling. Unfortunately the Ipswich specimens have no recorded GEOLOGICAL HISTORY
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history since evidently their particular significance was only very belatedly recognised. The unrolled condition of these specimens may be an indication of their having been obtained from the Coralline and not the Red Crag Basement Bed. At Ipswich also there are one or two portions of limb bones of larger cervid species, the more important is the proximal half of a metatarsal which possibly belongs to a megacerid, both Megaceros savini and M. verticornis are recorded from Felixstowe. Another bone is the shaft of a humerus. There are also some larger cervid teeth and an incomplete mandibular ramus with only the first molar preserved, about the size of M. verticornis, apparently from below the Red Crag, although the fossil condition slightly differs from most basal bed fossils.
The Crag Gazelle A horn core of gazelle-type found at Thorpe, near Norwich, was secured by H. B. Woodward and recorded in 1884. Other specimens were noticed at the same time and it appears that it was assumed this species was confined to the Norwich Crag. Remains of Gazella anglica are of some rarity, four are known from Norwich Crag, another two are labelled as from Norwich Crag, or just Norfolk, while the fossil condition is indicative of having been from the Red Crag basal bed and two others are unquestionably from below this deposit. One of these is the slender horn core of a female from Felixstowe, the other male: in addition three lower cheek teeth are known from the Red Crag, one is from Martlesham and another from Boyton. Some pieces of small limb bones are thought to belong to the Crag gazelle also some examples of astragalus smaller than those of deer which match the lower articular surfaces of a small tibia. The horn cores of this species are slightly curved backward unlike the lower portion of a smaller specimen Gazella daviesi from the Norwich Crag of Bramerton which is slender and straight and so far is unique. The mineralised Gazella horn cores from the Red Crag Basement Bed constitute evidence that this genus was living during the earlier terrestial stage of the Pleistocene and continued into the age of the Crag Seas but there is no indication that they survived into the Cromerian. T h e small size of the bones may be a reason for their apparent rarity in the Crag Sands, it is considered to be why smaller animals like foxes and Otters, etc., are rarely discovered since the remains are seldom noticed. T h e mammalian fauna of the Early Pleistocene is lacking in members of the antelope family and if one may judge from the number of fossils of the Anglian gazelle the species appears not to have been common. According to Flower and Lydekker in "Mammals Living and Extinct" the living representatives are typical Palaearctic desert forms of which there are about two
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dozen species, in most species both sexes have horns which are smaller in the female. T h e y are about two-and-a-half feet high. If the remains of G. anglica had been confined to only one horizon in the Crag Series they might have been regarded as indicating similar topographical and climatic conditions. As it is, there is the possibility that such conditions did exist during the Early Pleistocene since it has been established not only did climatic conditions vary but also the sea level. Another factor is that sandbanks formed in the Crag Seas were usually swept away and redeposited together with the fossils therein. It cannot be assumed that any fossil bones or teeth seen in situ in the beds are in the position in which they were originally deposited, had it been otherwise sundry bones of one skeleton should have been found within a very limited area. Only recently (March, 1970) there were several exceptionally large ribs discovered by Messrs. D. Collings and I. Cruikshank in Easton Bavents Cliff which must have belonged to a huge whale that presumably got stranded 011 a shoal between one and two million years ago. This is a remarkably rare occurrence and it remains to be seen if the storms of next winter during their usual attacks on the cliff will expose further remains of the same Leviathan.
The Cetacea When the myriad heavily mineralised and glossy fragments of whale ribs which occur with great frequency in most parts of the Crag Basement Beds and are unknown from the Norwich or Weybourne Crags are considered, cetacean remains are without question the commonest remains of pre-Pleistocene mammalian faunas. It is of considerable interest and scientific importance that similar fossils, together with teeth of sharks including the relatively enormous teeth of Carcharodon megalodon which are up to over four inches long, occur in Miocene deposits of Australia. There are oddly shaped bones which can only have belonged to skulls of immature whales of the larger species. Perhaps it is not generally understood that the bones of young mammals are formed of a series of units which, when the animal is fĂźll grown, become fused together to form one bone, for instance the articular surfaces of limb bones during the growing period are attached to the shafts by cartilage which ossifies as the bone lengthens: growing vertebrae are composed of several units, as was seen in an axis vertebra of a young elephant from the Stutton Brickearth which, when extracted from the matrix, separated into about seven units. So it is with skulls, which in man has about twenty individual bones separated by sutures which do not finally fuse for about twenty years, some of the cranial sutures are not completely fused until late in life.
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If, as may be presumed, cetacean fossils are generally the remains of stranded whales (as may be judged from the fact that foi some unknown reason schools of whales occasionally Strand themselves to the distress of locally resident mankind in these modern times), bones of the skeletons would become scattered by the action of the sea and the skulls of young whales, which are quite unlike those of land animals, would easily become disarticulated. Some of the fairly numerous vertebrae of whales from the sub-Crag basal bed are of immature animals since the inter-vertebral disks (articular surfaces) were lost before becoming mineralised. It is the "Cetotoliths" or petro-tympanics (ear-bones) of the Cetacea which are the most reliable fossils by means of which the various genera and species are determined, but regarding these there are some uncertainties such as dividing species because of differences in the size of specimens which may be due to the age of the whale at the time of death or to the sex. Whale teeth are not particularly well preserved, this is partly due to the peculiar structure of these teeth which, except in a few species, are devoid of the enamel which is an essential part of the structure of the teeth of land animals, they consist of a cylindrical core of osteodentine surrounded by a thick mass of cementum which gives the teeth their fusiform shape. In the fossils the cementum is generally pitted by attempts on the part of marine boring organisms to form cysts, such as the bivalve mollusc Saxicava arctica which normally bores holes in limestone and it is in these they normally live, the holes being enlarged as they grow. There is a factor on which no comment appears hitherto to have been made, it is that the boring agent might have been operative while the teeth were still in situ in the alveolus of the jaw and the pits represent the lower termination of the cysts, in fact this seems to be the most probable explanation of the phenomenon and might be an explanation of the absence of pitting on some teeth. The perforations were made before the teeth were mineralised since the hardening agent would render them resistent to boring mollusca. Quite a number of cetacean vertebrae are to a large extent covered with holes made by Lithodomus mollusca. There is a tendency for the outer cementum layer of the tooth to split longitudinally and sections separate and are lost exposing the dentine core, in some instances the whole may be lost and the curved rod-like core left bare. Names have been given to certain types of whale teeth some of these are similar to the teeth of living species but it is a curious fact that few of the toothed whales appear to have hearing apparatus and those with ear-bones seem not to have had teeth! This arises from the disadvantage of havingto determinefragmentary material. Regarding the cetotolites, the tympanics are the most abundant determinable fossil remains of whales and in some species they
PLATE
11
I ympanics of Balaena affinis, 1; B. primigenia, 2; B. insignis, 3 ; Balaenoptera definita, 4; Tooth of Balaenodon physaloides, 5; T o o t h of Orca citoniensis, 6.
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vary considerably in size but the variations in form are not very marked: some authorities have expressed doubts as to the validity of some determinations based on size alone. Balaena primigenia is considered to have a variable tympanic and no less than four variations were established. It is one of the few species of which periotics appear to have survived but the posterior process of periotics of sundry other species were found amongst unsorted boxes of various sub-Crag bones in the Museum basement at Ipswich, an example is figured which it is hoped may lead to the recognition of others and perhaps an unrecorded complete periotic (FIG. 26). T h e illustration is one of the smaller specimens and in the absence of the entire periotic of the same species it cannot be decided if it is from an adult whale. It is the most perfect example; the others are defective in some respect and the largest are incomplete, lacking the distal termination and have somewhat irregulär longitudinal grooves. The following list of determined cetacean species is based mainly on the petro-tympanics, the teeth and some vertebrae. It is compiled from Richard Lydekker's "Catalogue of Fossil Mammalia in the British Museum" and from E. T . Newton's "Pliocene Vertebrata of Great Britain". No comment can be made regarding this list because there has been no opportunity to make comparisons with the specimens in Continental institutions, in particular van Beneden's types at Brüssels.
The Cetacean Fauna:— Balaena Balaena affinis Owen B. primigenia van Beneden B. (Balaenotus) insignis van B. B. (Balaenula) balaenopsis van B. Megaptera Megaptera affinis van B. M. similis van B. M. minuta van B. Balaenoptera Balaenoptera definita Owen B. borealina van B. B. emarginata Owen B. (Plesiocetus) goropi van B. Cetotherium Cetotherium (Plesiocetus) brialmonti van B. C. dubium van B. C. hupschi ?—cf. burtini C. (Heterocetus) brevifrons van B. Herpetocetus Herpetocetus scaldiensis van B. Physeter Physeter macrocephalus Linnaeus (Cromerian Forest Bed)
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Eucetus Eucetus amblyodon D u Bus*. (This appears to have been a Miocene species) Balaenodon Balaenodon physaloides Owen Physeterula Physeterula dubusii van B. Physodon Physodon grandis D u Bus P. fusiformis D u Bus Hoplocetus Hoplocetus crassidens Gervaisf H. bourgerhoutensis D u Bus H. curvidens Gervais Hyperoodon Hyperoodon rostratus Müller Choneziphius Choneziphius planirostris Cuvier C. planus Owen C. packardi Lankester. Mesoplodon Mesoplodon longirostris Cuvier M. tenuirostris Owen M. gibbus Owen M. angustus Owen M. compressus Huxley M. floris Newton M. scaphoides Newton Squalodon Squalodon antwerpiensis van B. Delphinidae Orca Orca citoniensis Capellini O. gladiator Gray (Cromerian Forest Bed) Pseudorca Pseudorca crassidens Owen (Cromerian Forest Bed) Globicephalus Globicephalus uncidens Lankester Delphinapterus Delphinapterus leucas Pallas (Cromerian Forest Bed) Delphinus Delphinus delphis Linnaeus (Norwich Crag, etc.) • D ü r i n g July, 1970, the vertically split half of a whale tooth with remains of its original sandstone matrix attached was discovered to be the missing half of a tooth in the Geological Survey M u s e u m , of Eucetus amblyodon. T h e y were separated for well over a Century. f P r o f e s s o r Henslow had a Boxstone enclosing the core of a tooth determined as H. crassidens which was cut into sections, three of these are in the British M u s e u m , South Kensington. T h e r e m u s t be the remainder of the sections in some other collections but none have been detected so far. It seems highly probable that the tooth in a Boxstone at Ipswich is of the same species which is shown to be of Miocene origin.
I
2. i m S
PLATE 12
whaksieWTh°5 the ptosteri°r Process of the periotic of one of the sub-Crag whales. The penot.c and tympanic together form the principal parts of heV ear Uin Cetacea and although the bonesfiguredabove have been found n0t vTrv S Collect'on/ they P^viously been recognised They Vary in size and form in different species, some being much larger
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Tursiops
Tursiops (Delphinus) tursio Bonnaterre Phocaena Phocaena communis Lesson (Cromerian Forest Bed)
It may be well to regard this list as provisional, there are said to be few vertebrate palaeontologists in Europe and presumably there are fewer interested in the study of Miocene and Pliocene whales but it would be a good thing to have a revision of the subRed Crag and Red Crag cetacean remains. Many of the species recorded have been noted from Continental Pliocene formations and only a very few Suffolk cetotolites have been recorded from the Coralline Crag Sands and these are easily recognisable from the State of the unrolled surface and different degree of mineralisation. All the cetotolites from the basal beds of both the Coralline and Red Crags are highly mineralised, usually some shade of brown and a few almost black; the majority are rolled to some degree while a few of the darker specimens are rolled to a much greater extent. Presumably the latter are older but their fossil condition is such that they are not easily determined. A dark coloured tooth of Eiifetus amblyodon in the Geological Survey Museum, which has been sectioned, is partly encrusted with Miocene sandstone a fact which raises a suspicion that the much rolled dark petro-tympanics may be of a similar age. There are in collections quite a number of much rolled whale vertebrae and some of these appear to have been partly decomposed before becoming mineralised, being more or less hollow due to the partial decay of the cancellous tissue of the interior. A number of vertebrae which have lost the inter-vertebral discs, due to the immaturity of the animal at the time of its death, have one, or both of the exposed faces of the bone pitted with the crypts bored by Lithodomus molluscs, some of these are blackish but it is not claimed that this necessarily is always of significance. (Experience has shown that geologically recent bones are blackened during prolonged burial in black ooze rieh in hydrogen sulphide and on rare occasions patches of iron sulphide have been observed on such bones, the subsequent oxidation of the pyriteous matter would possibly contribute to the mineralisation of a fossil bone.) Analysis of sub-Crag bones proves that iron is present and is no doubt responsible for the brown colour of these fossils. Quite a number of caudal vertebrae become considerably rolled after mineralisation to such an extent that any specific determination cannot be made, but it seems possible that they originated in the Miocene epoch. None of the bones which certainly belong to the Pliocene are rolled to the same extent and the presence of cetacean remains in the Miocene of Australia in a similar fossil condition to those from below the Red and Coralline Crag lends strength to the claim that the non-Pliocene bones are Miocene.
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Cetotolites of Balaena borealina have been recorded from below the Coralline Crag of Sudbourne and the Red Crag of Boyton which being quite close to the older Crag there can be little doubt that it was derived from thence. Vertebrae attributed to this species are similarly derived, probably from the reduction of the Sutton Island into the Red Crag around Woodbridge. Megaptera afĂ&#x;nis and M. minuta are also recorded from the Pliocene Crag Sands and the latter's tympanic is said to closely resemble that of the existing M. bĂśops. Various vertebrae from the Woodbridge area were thought to be referable to Balaenoptera goropi and two tympanics and four periotics attributed to B. borealina are recorded from the same area. B. emarginata is probably the whale most commonly represented if the number of tympanics is anything to go by. In a series of over one hundred cetotolites from Bawdsey and Felixstowe, those of this species were the most frequent. A similar tympanic from the Miocene of Victoria, Australia, is in the British Museum. Cetotherium brialmonti and C. dubiurn also from the same area are recorded and may perhaps be regarded as two of the rarer species. Imperfect axis vertebrae of C. hupschi and of C. brevifrons are recorded and one of the latter species should be in the Ipswich Museum. Unfortunately most of the Ipswich Crag bones were dumped into boxes for the removal from the Old Museum in Museum Street to the New Natural History Museum in High Street and apparently never unpacked with the result that the labels decayed and it is not now possible to distinguish to which species the various axis or atlas vertebrae were originally assigned. Physeter dubusi is represented by one incomplete tooth. The largest teeth at Ipswich are almost as large as those of P. macrocephalus but they have been determined as belonging to Eucetus amblyodon. These teeth may have a diameter up to 78 mm. (2\") and a proportionate length, the osteo-dentine core measures only 25 mm. (1") and the middle is granular. The greatest diameter is about one-third down from the apex. A periotic thought to belong to this species is recorded from Felixstowe. The following species appear to be represented only by fossil teeth:— Balaenodon physaloides, Physodon grandis, P. fusiformis, Hoplocetus crassidens which is also known from the Miocene of Malta, H. borgerhoutensis and H. curvidens. Some teeth have enamel crowns. The Delphinoid cetacea are chiefly represented by periotics also by some tympanics. Newton figured four small periotics and one tympanic which had not been identified with any species, these are fairly numerous in collections with the largest series at Ipswich; they do not exceed 30 mm. (l j") in length. Other periotics of a generally similar form are much less common, only one or two of
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each genus is known, they measure about 60 mm. (2J") and represent the following genera:— Eucetus amblyodon, Hyperoodon, Orca and two Ziphoids—Choneziphius and Mesoplodon. T h e Ziphiinae, or beaked whales, have a number of bones in the anterior part of the skull fused together to form an elongated solid mass, the Rostrum. These rostra vary considerably in form, some are more elongated and are attributable to whales of a slender form, the remainder are poportionately bulky and are of three species only, Choneziphius planirostris, C. planus, and C. packardi*. One other periotic is referred to Mesoplodon Icmgirostrisl which represents one of the slender types of rostra, of these M. gibbus is the most common species. All the rostra are completely mineralised but they vary in colour from a yellowish to a dark brown and some are much more rolled than others. M. longirostris appears closely to resemble the living species M. australis. In the British Museum (Natural History) there is the middle portion of a Ziphoid mandible with the space behind the Symphysis filled with hard sandstone similar to the Boxstones and is indicative of a Miocene origin for this species, the mandible of M. australis is comparable with this fossil which is figured, see FIG. 27A. FIG. 27B illustrates a tooth of Carcharodon megalodon partly enclosed in similar sandstone which is in the same institution, Skeletal remains, apart from vertebrae, are uncommon: at Ipswich there are two fragments of Mesoplodon? mandible and an ulna. There are in other collections incomplete ulnas of other undetermined larger species of whales and from the Norwich Crag Sands one of the hyoids of one of the medium-size species was discovered by the brothers D. and P. Long. Only part of one other specimen is known. These are indigenous fossils. T h e hyoids are a forked system of small bones situated in the throat at the base of the tongue. While it is not possible to distinguish from the fossil condition of sub-Crag bones or teeth whether they belong to the Pliocene or older epochs it appears to be obvious that all have undergone a similar process of mineralisation under like conditions. If one is to judge from the phosphatised and partly mineralised late Pleistocene elephant teeth trawled up by fishermen during the •Edward Packard senior was owner of the Ipswich Fertiliser factory and played a part in the formation of the first Museum built in the town and was Chairman of the Committee for some years. T h e r e had been an earlier Museum in a room of the old T o w n Hall (1790) which was established by the noted lepidopterist and rector of Barham, the Reverend William Kirby. Kirby Street in Ipswich commemorates his authorship of "British Butterflies and M o t h s " but there are few, if any, of the local Citizens who know this, or that Packard Avenue was named for Edward Packard junior, knight, who was also a Chairman of the new Museum.
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last Century from the sea floor off the Essex coast and now in the Colchester Natural History Museum, this process obviously takes place on the bottom of the sea. As remains of land mammals became mixed with those of marine mammals it is clear that the rise of sea levels brought about the destruction of previously formed deposits laid down in river Valleys, lakes, etc., and the remains of animals, already perhaps to some degree mineralised, derived through coastal erosion were incorporated in the new marine deposit together with previously derived fossils from older formations which had a similar history. Fossil bones, etc., of indigenous faunas in any epoch differ in the degree of mineralisation and rarely exhibit indications of rolling as is shown by the remains of the coeval fauna of the Red Crag. No such fossils have been discovered in the Coralline Crag other than uncommon cetacean bones. T h u s it is that the assemblage of varied fossils in the basal bed below the Red Crag implies a repeated cycle of alternating terrestial and marine phases throughout the whole of post-Cretaceous times, while the former existence of formations once thought not to be present in the sequence of East Anglian strata are also indicated. A badly preserved posterior fragment of a large cetacean mandibular ramus was discovered below the Red Crag at Coronation Drive, Felixstowe, when trenching for the sewers for a new estate in 1953. It is at Ipswich and is completely mineralised. Squalodon antwerpiensis is one of the rarer species which is represented by only one or two teeth, on the Continent remains of this genus are found in Miocene strata. Monodon monoceros is known only from the Cromerian Forest Bed Series by a fragment of one of the elongated tusk-like maxillary teeth. T h e habitat of Monodon is the arctic regions. Halitherium canhami Flower is based on the remains of a skull comprising the palate with the broken stumps of some teeth and some of the bone structure above the nasal passage. It is very badly rolled and is obviously very ancient. H. canhami appears to have some resemblance to H. schinzi but is larger, the teeth are much like the molars of Hippopotamus with which there may be some ancestral link: thick, short massive-looking fragments of ribs also occur. T h e species was named after the Reverend Canham who resided at Waldringfield, a parish next to Newbourne where large pits were opened and he doubtless had influence with the parishioners who worked there which enabled him to form two large collections which were purchased by Sir Richard Wallace, a patron of Ipswich Museum, and were presented to that institution. Canham was the incumbent of the parish of Ramsholt across the Deben and there can be little doubt that he secured many fossils from that parish, and also from Shottisham, Hollesley,
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and Alderton. It is unfortunate that very few of his specimens have any record of the site from which they were obtained, but most came from within a two mile radius of his home. He did make a third collection of less importance. T h e Halitherium had a pair of tusk-like upper incisors and in Ipswich Museum there is a portion of an unidentified large incisor with a rather rounded sub-triangular section which may belong to this species. T h e type of this species is from Foxhall and was undoubtedly derived from the Miocene. Molar teeth of this Halithere are preserved in the Reed Collection in the Yorkshire Museum.
A New Crag Mammal A fragment of bone heavily mineralised has recently been discovered by G. L. Ransome at Bucklesham, the fact that it has been subjected to considerable rolling which has modified the contours of the articular facets will prove a handicap in its determination (FIG. 28). T h e fossil consists of the distal end of a fused radio-ulna* of a rather small mammal apparently not previously recorded from the Red Crag basal deposit. Its condition indicates
FIG. 2 8
Mineralised radio-ulna of a small mammal not previously recorded from the Red Crag basal bed. It probably belongs to a pre-Pliocene epoch. *For the benefit of readers unfamiliar with anatomical (osteological) terms, the radius and ulna are two bones of the fore limb of most mammals and in man are situated between the elbow and wrist and are quite separate which enables free rotating movements to be made. In some mammals the radius and ulna are free during the immature years but as the body weight increases and the radius having to bear the greater part of the bĂźrden, the ulna becomes united with the radius, i.e., become fused together and take part in supporting the weight, the fore limbs supporting much more weight than the hind legs. T h i s occurs in pigs, hippopotamus, and rhinoceros. It is odd that in our largest living land mammal, the elephant, the radius and ulna remain free and the ulna has the major part in bearing the relatively immense weight of the large head, trunk, and tusks, the upper part of the radius is relatively very small and the distal (lower) end disproportionately large. In horses, deer, and oxen, the lower part of the ulna having become non-functional, perhaps due to the need for speed to escape predators, is m u c h reduced in length and only the upper part remains and is permanently fused to the radius as anchorage for the main tendons. In other genera the ulna is functional to some extent but in a few the lower end is reduced.
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it originated from some older formation, presumably a period in which, among the mammalian fauna, there were a great number of imperfectly known and unfamiliar animals, thus there is a possibility that it will be very difficult to identify. The sub-Crag Fishes Apart from some vertebrae most of the sub-Red Crag fish remains are teeth and by far the greater number represent various members of the shark family from various epochs, some teeth of the smaller species are in an almost perfect State of preservation and are indigenous teeth which in collections became mixed with the derived teeth, probably because it was not realised that they had any significance. With few exceptions the other teeth are to some extent rolled and a number so much as not to be identifiable, amongst them, however, the rostral teeth of Pristis (sawfish) have been recognised. Of exceptional interest are the well preserved demi-bodies of an Eocene genus, Halicopsis spp. together with the heads of larger species. These are coloured brown in contrast to the grey of similar fossils taken directly from the London Clay where fossils of quite large fish have been discovered and a series of consecutive large vertebrae from Bawdsey were determined as belonging to one of the Scombroids. The odd thing about these fossils is the fact that the bodies have been bitten in two leaving the head and from a quarter to a third of the body in a remarkably good condition, usually with each scale clearly defined though the head is generally damaged. The heads, without any particular amount of body, are often distorted and this may be due to the pressure of superincumbent rock. It is very difficult to imagine how these comparitively soft bodies came to be preserved, but one may imagine larger predatory marine animals such as sharks pursuing a shoal might bite some fishes in two, a near miss so far as getting the whole fish, the uneaten portion would drop to the sea floor where some unknown preservative agent substituted, molecule by molecule, stone for flesh! Incidentally, perhaps it is not generally known that scientifically sharks are not considered to be fish by some authorities, and perhaps a description of the dental arrangement of these Selachians may be of use to readers unfamiliar with these creatures. Had nature made a similar provision in mankind there would be no need for dental surgeons. Sharks generally have a battery of teeth in curved parallel rows, they are larger in the centre and become progressively smaller outward. In use the outer marginal teeth hinge outward and are functional, as these are detached for one or other reason the teeth in the next row move forward and become functional. The teeth in some larger sharks have serrated (saw-like) edges but the unmodified edges on the teeth of other species are quite sharp. However, there are a few sharks which
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feed on mollusca which have a sort of pavement of nodular crushing teeth. The skins of sharks are covered with small closely-packed nodular bodies in place of the scales of most true fishes. These are pointed and the natives of the Pacific Islands used them as rasps. The skeletons are cartilaginous but from the fact that vertebrae of Carcharodon megalodon from the Miocene, and of other species, occur as fossils in the Crag basal beds, they are evidently partly ossified. Teeth are considered to have evolved from the scales around the mouths of fishes, probably those scales of species with a bony foundation, such as the enamel coated scales of the Ganoidei which gradually migrated into the mouth and evolved according the habits and environment of various genera throughout the ages, to serve the varied needs of different species such as tearing, cutting, crushing, grinding or just masticating. The shark family and related genera have been a very successful group with a geological history of some three hundred and fifty million years. Cetorhinus maximus, the basking shark, frequents arctic seas but sometimes ventures as far south as the fortieth degree of latitude thus any remains of this monster have no bearing on the climate of the Crag period. The age of the very few claw-like "clasper-spines" in collections is uncertain because of the lack of data regarding their position, whether in or below the Red Crag, if from the basal bed they could be relics of the pre-Red Crag cold phase, but it is IF! This member of the shark family grows to whale-like proportions and like some of the cetaceans feeds on plankton and has no teeth to become fossil. The claspers are confined to the male of the species and are used in mating. The rays are represented also by the teeth which are generally elongated more or less rolled fragments of the sexagonal teeth from the middle row, which have transverse parallel ridges. There are about seven of these teeth with marginal rows of smaller teeth, as the animals grow the median teeth lengthen to about eight times the width and they are packed closely together like a well laid pavement. The largest teeth are of Myliobatis toliapiciis from the middle Eocene. In recent years a search through boxes of small bone fragments and other assorted items revealed short pieces of the poisonous saw-edged caudal spines of M. serratus. These are not common and do not previously appear to have been noticed, this is an Oligocene species. Embedded in the skin of rays are numbers of button-shaped bony scutes with a thorn-like spine in the middle, these are fairly common objects in, or below the Crag. Some belong to Raia clavata (Pliocene). Aetobatis also has pavement-like parallel teeth but they are arched and also of Eocene origin. Zygobates cf. woodwardi is a Miocene species which Owen records as a derived Crag species,
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it seems to be very uncommon, the middle teeth are smaller than those of Myliobatis and the next row on each side is nearly as large with the marginal teeth but proportionately smaller as in the latter genus. Rounded yellowish objects, with minute blackish spots all over and often with remains of black bone attached are remnants of the dental plates of Chimaeroid fish ("rabbit fish"). T h i s family has a geological history going back some one hundred and eighty million years to the Jurassic and has living representatives, one, Chimaera monstrosa is found in the Mediterranean. T h e dentition is uniquely unlike other denizens of the seas and the fossils are not teeth in the general sense of the term but are known as "tritors"; they are derived from the Eocene or the Oligocene. A fragment of a fin spine from Foxhall has been figured by Newton and referred to one of the cat-fishes, Arius, it is from the Eocene and appears to be unique as a sub-Crag fossil. Certain conical and peg-like also hemispherical pale-coloured teeth resemble those of Chrysophrys auratus but are larger. In this species the longer teeth form a marginal row with the rounded teeth closely packed behind, other bean-shaped teeth are situated to the rear; none of the latter appear to have been found in the Crag beds although the other types are fairly common. These teeth have been recorded from the Pliocene Coralline Crag, the Red Crag basal bed and the sands above, the Weybourne Crag, and the Norwich Crag. T h e y have also been recorded from the Crag-like deposits of Bridlington, Yorkshire. T h e family to which Chrysophrys belongs originated in the Eocene but this genus ranges from the Miocene to our recent seas. In some collections the longer teeth have been labelled "wolf fish", Anarrhicas lupus, but they lack the labyrinthoid structure of that genus. A wolf fish tooth has been recorded, however, from the Coralline Crag of Gedgrave. T h e r e are in the British Museum (Natural History) the united pharangeal bones of a labroid fish from the basal bed of the Red Crag which were referred to Labrus by Smith Woodward: Newton thought it possible some of the Chrysophrys teeth may belong to this species, but this is considered doubtful. T h e Labridae (wrasses) are represented in the Eocene, Miocene, and Pliocene strata and are represented in the Red Crag basal bed by the grouped laminated teeth of Phyllodus, possibly of three species. T h e teeth are thin layers one above the other like a pile of plates, they are slightly concave above and convex in the lower jaw. T h e middle teeth are three in number, the first is " D " shaped and the others oblong with rounded ends, the whole ringed with two rows of smaller teeth forming a horseshoe-shaped group. Newton recorded one fragment of the rostral spine of Coelorhynchus rectus from the Red Crag basal bed at Woodbridge, it is
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311 now known as Cylindracanthus rectus. This rapier-like rostral process is longitudinally ribbed and is hollow but in the posterior part the cavity is divided by a septum; when entire it would be about 25 cm. (10") long and is proportionately slender. Latterly other short portions of these rostra have been discovered in unsorted boxes of small specimens. These fossils have an Eocene origin. Notidanus gigas is represented in the Red Crag basal bed, in the Red Crag sands, and the Norwich Crag, but the teeth are uncommon both in numbers and in their character. On a long base are a series of saw-like cusps which diminish in size laterally, there can be up to nine points on each tooth. The family to which it belongs originated in the Jurassic and has living relations. Lepidotus and Pisodus are twofishesrepresenting different families which have hemispherical crushing teeth. The former belongs to the Ganoidei which has bony rhomboidal enamelled scales and such scales do occur very rarely in the Red Crag basal bed; they have been picked up together with teeth of the smaller sharks at "The Rocks" in the Deben estuary near Waldringfield. In addition to the dome-shaped teeth there are smaller flattened conical teeth, which like Phyllodus are successional but are unusual in that the new teeth develop in an inverted position and have to rotate through 180° to become functional. Lepidotus is a Jurassic species and some of the teeth at Ipswich supposed to have been found in the Crag are indistinguishable from Jurassic specimens in that Museum in size and fossil condition and do not compare with teeth actually from the basement bed. Sphaerodus is a synonym for the genus. Pisodus is an Eocene species and its teeth are more likely to occur in the basal bed of the older Crag strata. Acipenser (sturgeon) is represented below the Red Crag by dermal plates, or scutes, which do not Cover the body as articulated scales as in other Ganoids but in parallel rows along the back and sides, the mouth is tubulär and toothless. Scutes of Acipenser toliapicus have been recorded from the London Clay of Sheppey and a species is known from the Oligocene. The genus is known also from the Miocene but it is not possible to determine the age of the fossils found below the Crag at present. Caviar is made from the roe of the female and isinglass from the swim-bladder, some species grow to a length offifteenfeet or more. Gyrodus and Pycnodus are also members of the Ganoidei and are covered with rhomboid enamelled scales and both have parallel rows of crushing teeth of varied pattern, complete vomers with teeth have been found, these are bones of the skull forming part of the roof of the mouth. The former was a deep bodiedfishlike a
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plaice, but thicker and without the fringe of fin, and swam normally. It is a Jurassic genus. Pycnodus had a more elongated body and is from the Eocene. A fish tooth of acutely pointed form, somewhat like those of a pike but probably of a marine species was discovered by John Norman in the Red Crag when Freston Hill was widened, it has not so far been named. It is about 10 mm. in length, black and thoroughly mineralised.
THE INDIGENOUS CRAG MAMMALS Reference has already been made to the Crag elephant, Archidiskodon meridionalis, the Crag horse, Equus robustus, and a smaller species, also to Gazella anglica, these evidently evolved during the vanished Continental stage of the Early Pleistocene destroyed by the incursion of the Red Crag Sea. This origin presumably applies to the various genera and species of the deer family of which partly mineralised, usually shed antlers occur in the Red, Norwich, and Weybourne Crag Sands, also in the Westleton Beds (sensu stricto) which are a thick series of marine beach pebble deposits. T h e Crag Sands contain a mixture of land and marine mammalian remains and the fossil condition of these indicates that they are mainly coeval with the deposition of the formations, the exception being the Mastodon teeth in the Norwich Crag the fossil condition of which is more akin to fossils from the basal beds of the Coralline and Red Crags. Since the Cervid fauna is found in all the Crag Series and with one exception in the Cromerian Forest Ă&#x;ed Series, it will be best to deal with it as a whole, excepting only those species not so far recorded from Red Crag.
The Megaceridae The earliest recorded specimen of this genus is Megaceros verticornis from Trimley St. Mary consisting of the shed beam of an antler of a well-grown stag which had not reached fĂźll maturity, the specimen is in the British Museum (Natural History) and escaped the attention of Dr. A. Azzaroli (now Professor at the University of Florence) when he was preparing the paper on " T h e Deer of the Weybourne Crag and Forest Bed of Norfolk", Bulletin of the British Museum (Natural History) Geology, Vol. 2, No. 1, 1953. This species had enormous antlers of which the most complete example, although discovered at Pakefield in Suffolk, is preserved in Norwich Castle Museum but not exhibited. T h e shed base with a fresh looking fracture indicating that the specimen was originally more complete, and also from Trimley was presented to the Ipswich Museum by Miss J. C. N. Willis, M.A. ; it was in her father's collection. The species is also recorded from Felixstowe. Also at Ipswich is the top of a skull, of which the exterior is rather badly battered, thought to belong
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to this species, unfortunately it has no history having been discovered in a box of undetermined bones from the old Museum. It could also have come from the Trimley pit but there were numerous other pits opened in the district. The inner surface of the skullcap is perfectly preserved. Another member of this genus, M. savini, is recorded from Felixstowe, it was discovered during trenching Operations for a new housing estate. This was not a shed antler and the presence of part of the pedicel indicates the stag was either prey to a predator or was drowned. The third species, M. daickinsi, appears not to have been a Crag species, at least so far there has been no evidence of its presence earlier than the Cromerian. (Sir William Boyd Dawkins described a number of Crag and Forest Bed deer antlers. He worked on the Geological Survey and later became Curator of Manchester Museum.) These two members of the family had less remarkable antlers, those of M. savini had a relatively long slightly curved beam with no palmation, the brow tine was expanded and in extreme instances formed aflatthin palmation. Part way along the beam was a low flattened expansion from the upper surface extending upward and forward, this feature is sometimes further from the burr and close to the angle where the beam bends upwards and terminates in a fork formed of a larger and a smaller tine: there is another tine at the bend. (Mr. Savin was an indefatigable collector who ranged along the whole East Anglian coast where the Forest Bed outcropped at the base of the Norfolk and Suffolk cliffs. He amassed two large collections.) It would appear from the number of portions of antlers in the collections that it may have been the more common species with a ränge in time equal to M. verticornis. The fact that M. savini appears to be rarer in the Crag Sands is probably due to the lack of Crag outcrops along the coast subjected to attacks by the sea whereas from Lowestoft to the north and north-west erosion has been very severe. The antlers of M. dawkinsi are comparitively simple in a different way, there was no brow tine proper but occasionally there may be a small prominence, the beam was short and in the younger stags had a slight curve. In adults the beam rapidly expanded to form a palmation with up to six broad based tines. Portions of skulls with the antler pedicels and sometimes the base of antlers are in the Norwich Castle and British Museums representing all three species. The largest of the family was the miscalled "Irish elk" M. giganteus, which is not an elk neither was it exclusively Irish, its
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remains have been found in Essex and Suffolk as well as other parts of the country, but always in deposits of more recent geological age. Azzaroli described and figured a number of abnormal antlers under the name "Cervus obscurus" but subsequently, in a personal communication he stated that he had come to the conclusion that the specimens were actually malformed antlers of M. verticornis. Having examined the specimens this is found to be true. An antler beam with the bases of the tines from the Norwich Crag was described by Dawkins: for this new species he proposed the name Cervus falconeri in honour of Dr. Hugh Falconer who described the numerous fossil elephant and other remains from the Siwalik Hills of India where there is said to be some thousands of feet of mammaliferous deposits representing a long period of time. Shed antler bases of "Falconer's deer" are among the commonest relics of the extinct Crag species but it does not appear to be represented in the Cromerian Fauna (FIG. 29).
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There are four fairly complete antlers of this species, Dawkins' type is in the British Museum, another recently discovered at Easton Bavents by Ian Cruikshank of Reydon, is in the Institute of Geological Sciences (Geological Survey), and constitutes the most complete specimen so far discovered. It is not a shed antler the pedicel and part of the frontal bone are preserved, the brow tine is almost intact and part of the curved section above the upper (bez) tine is present. Like the type it belonged to a young stag. There are two at Ipswich, of these the most important is a shed antler of a more mature animal from the Red Crag Sands of Bramford which was discovered during the investigations of J. Reid Moir in the early 1920s. With this specimen was the base of another slightly larger antler and a smaller specimen: at first it was thought that this was from a much younger stag of this species, but it was eventually determined as Dama nesti nesti. There is also a portion of another antler of another species, E. sedgwicki, which was named after Adam Sedgwick, who is also commemorated at Cambridge by the Sedgwick Museum. All these fossils came from the former Chalk Pit or the Brickworks Pit at Bramford, where, unlike the larger pit, the Crag rests on London Clay, as is normal and with a vertebra of a whale, a fragment of a bear canine, and a tooth of a porcupine from an aged animal constitute the entire indigenous fauna for the locality. These antlers are now referred to a new genus Euctenoceros Trouessart. E. falconeri and E. sedgwicki were proved by Moir's discovery to be far older than was previously believed, the latter species having been supposed to be solely a Cromerian Forest Bed deer. Another early record for this genus is one tine from an antler of E. tetraceros from Felixstowe Red Crag. This species seems to be uncommon as with the exception of the Felixstowe specimen from the Red Crag only about three others have been observed, all from Norwich Crag. T h e best existing specimen consisting of a portion of beam thirty centimetres (twelve inches) long with a similar length of a tine lacking at least three inches from the tip, must have belonged to a fully mature stag. This was noticed on tbe spoil heap from a trench at the southern end of Wangford main street (the Lowestoft road), in 1961. T h e section of the beam and tines is oval like the complete antlers in the British Museum (Natural History) but all the Forest Bed antlers determined by Azzaroli and originally figured by Newton, have a circular section with a grooved surface and an altogether robust aspect quite unlike the Continental antlers in the British Museum mentioned above which have a smoother surface (FIG. 29). Lydekker, in the British Museum Catalogue mentions the upper terminal tine of an antler from Norwich Crag as possibly belonging to this species, but it undoubtedly belongs to E. sedgwicki, the specimen being precisely similar to others from the same Crag in the Ipswich Museum.
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The antlers of these "comb-antlered deer" are comparatively easy to distinguish, in E. falconeri the beam below the brow tine is more or less sub-triangular in section and above the brow tine there is a kind of twist and it is flattened. At a varying distance above the brow tine there is a small (Faccessory) tine which is not always present: at the top of the beam it forks, with a tine projecting forward, and the continuation of the beam becomes broader and is usually curved. T h e upper termination is missing in all Crag specimens and is unknown (FIG. 29). With E. sedgwicki the beam below the brow tine is nearly circular and there is a greater distance between the burr and the tine, the beam is long and flattened and terminates in a fork, in the adult stage there are three large tines which sub-divide into two, three, or more points. A distinctive feature of this species is the usually markedly undulating character of the tines when viewed edgewise, E. tetraceros of the type from the French Upper Pliocene ( = E a r l y Pleistocene?) had an antler which varied according to age, a fiveyear-old stag had the brow tine branching off quite close to the burr and two other tines, with the uppermost curved upward. In a stag a year older the brow tine diverged slightly higher and an additional tine formed, the tips of all the tines turn up at the tips. Two specimens have been found in the Westleton Beds of Holton, four miles west of Wangford, one was a very short section of antler in a brittle condition from the Upper part of the beds where doubtless it had been acted on by percolating water. T h e other is larger and probably from a young animal, it is of a black stone-like nature and came from the lowest level worked, well below the water-table in a pyritised zone with shells. Fossils of this type are known from the Crags of the opposite coast of the North Sea where, in Holland, they are known as "Black Bones". They are particularly hard and clink when tapped with metal. Another species of this genus is E. ctenoides which was larger than the others with the exception of sedgwicki. The antlers of this stag were relatively straight and inclined backward with the brow tine projecting forward almost in line with the beam, as a consequence of this the burr is oval whereas in most deer it is more or less circular, at this point there are usually a group of small prominenaces on the upper surface. T h e most complete antler of a fully grown adult stag consists of part of the beam with the lower portions of two tines almost as thick as the beam. T h e length of the tines is unknown but to judge from thickness of the lower parts they must have been quite a length. B. C. Belson of Cambridge very generously parted with a pair of antler bases with pedicels and portions of the frontals capable of partial restoration. T h e study of this specimen enabled a determination to be made of the position of the antlers in relation to the skull of this little known species (FIG. 30).
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FIG. 30
Antler bases and frontals partly restored, A. Side view of right antler base, B. Restoration based on two specimens, C. Euctenoceros ctenoides.
The second Ipswich antler of E. falconeri has a broken beam with a small portion lost, as also is the base, judging from the fresh-looking fractures it must have been complete and was broken when excavated and some fragmerrts were not collected. It has no history but obviously came from Norwich Crag. A much less complete malformed antler is believed to have been taken from Red Crag at Martlesham. Shed bases from Norwich Crag are relatively common and are in all probability also in the Westleton Beds but excavation by machinery does not favour fossil collecting; bases of E. falconeri and E. sedgwicki have been found in material brought up from the low level pyritised zone at Holton. Shed antler bases of these species have been found in Easton Bavents Cliffs, also cast ashore on Walberswick beach. The smaller Crag and Forest Bed deer were referred to Cervus etueriarum by Lydekker and Newton, a first year "pricket" with the pedicel was named C. rectus by the latter author but it is most probably the first antler of a young stag of Dama nesti nesti to which species C. etueriarum is now referred (may one say it is good not to have to pronouce that name again?). The earliest Red Crag record has already been mentioned and the Bramford specimen remains unique as the only example so far discovered in that formation. There is no known record from Norwich Crag
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but there have been several portions of shed antlers from the Westleton Beds of Holton. These are from various levels but most notable are portions of an antler from the low level pyritised zone which was broken by the impellers of a centrifugal pump used for raising gravel. Holton has yielded a number of cervid fossils which are unlike anything with which they can be compared, these include a number of pedicels with remains of the antlers too fragmentary for determination; there are also portions of antler beams which are exceptionally straight and unlike any Crag or Forest Bed species. Amongst the Holton bones are specimens typical of the "Black Bones" previously mentioned. Reputedly from the Forest Bed Series of the Norfolk coast are incomplete antlers and portions of others of Libralces gallicus, and most of these fossils are quite stone-like and perfectly black. For this reason it is considered that these "Black Bones" fossils, if indeed they were collected from one of the Forest Bed Series, were probably derived from the Weybourne Crag. Düring a recent re-examination of Crag and Forest Bed fossils, specimens have been observed with labels recording them as from the Forest Bed, but remains of shelly crag adhering to the lower surface and traces of dark clay above prove that they were taken from the surface of the Weybourne Crag where it was in contact with an overlying Forest Bed Stratum. It is beyond question that the Weybourne Crag must originally have been a substantially thicker deposit and that there must have been a considerable amount of erosion previous to the deposition of the Forest Beds. Therefore it is inevitable that many Crag mammalian fossils were re-deposited in one or other of the new deposits and has resulted in a confusing mixture of faunas. Düring the last twenty years evidence has come to light that L. gallicus is an older species than was supposed and the first evidence of this was obtained at Holton when some fragments were preserved by some of the staff. These pieces when reassembled formed a small portion of a skull with the pedicel and the lower part of an antler indistinguishable from the Forest Bed fossils. It is evident that most of, if not a complete skull with antlers was present in the pyritised zone and was unfortunately broken into fragments by the pump. T h e fact is that large bones in the lower levels were sometimes a considerable nuisance as they blocked the p u m p which had to be dismantled*. Since this discovery other shed antler bases of this species have been obtained from the Westleton Beds and the Norwich Crag of Easton Bavents.
• D ü r i n g the p u m p i n g of gravel in the Gipping Valley at Bramford Road m a n y years ago there were similar occurrences, on one occasion the stoppage was due to the skull of a Woolly Rhinoceros.
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Another elk, L. latifrons, a larger species, occurs in the Norfolk coast deposits and has yet to be recorded from Suffolk, the antler remains are similarly very heavily mineralised. In Azzaroli's Bulletin on Weybourne Crag and Forest Bed deer two other species are mentioned, L. reynoldsi and L. minor, the former being regarded as the largest cervid. In a personal communication he stated that both the larger species should be included in L. latifrons and the L. minor was thought to be the female! of L. gallicus. Specimens have been trawled up from the North Sea floor at the Dogger Bank and elsewhere. This genus, together with the Crag deer (of Villafranchian age), the Crag horse, Equus robustus, and the Crag elephant, Archidiskodon meridionalis, all became extinct with the oncoming of the Cromer glaciation. The red deer, Cervus elaphus, is not a Crag species but the incomplete shed antlers are not uncommon in the Forest Beds, the species has always been recorded with some doubt because no example of the characteristic cup-like grouping of the upper tines was thought to be present. Dßring a recent examination of deer antlers in the Norwich Castle Museum a portion of the upper part of such an antler was noticed, this should remove past doubts as to the presence of red deer in the Cromerian Forest Bed Series. This, however, provides no answer to the question of how this species happens to be present in a formation with a Villafranchian deer fauna. It is this factor which led Azzaroli to attribute part of the Forest Bed Series to the Hoxnian Interglacial. This cannot be so as the whole of the Cromerian Forest Bed Series is buried below the Cromer Till which was deposited as a result of the Cromer Glaciation. The teeth and bones of the woolly elephant, Mammuthus primigenius, provide a similar problem. The presence of antler bases very similar to those of Dama clactoniana from Hoxnian deposits led Azzaroli to declare that the Cromerian Upper Freshwater Bed was post-Villafranchian. This may well be so but as this bed is below the Cromer Till it cannot possibly be Hoxnian. Comparison of the Cromerian fossils with the more complete antlers of this species from Swanscombe has provided no reason for supposing a different species is involved. Two rather unsatisfactory fragments of antler bases from the Holton Westleton Beds are more like D. clactoniana than any other species but only the discovery of better specimens can confirm this. Tapirus—Tapirs The presence of both lower and upper teeth of Tapirs in the Basement Bed of the Red Crag and probably of the Coralline also constitute evidence of tropical climatic conditions during at least some part of the Pliocene. Like the Mastodons the crowns only of the teeth have survived and no bones referable to this genus are
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known. There are two species T. priscus and T. arvernensis representing the lower and upper Pliocene, members of the family were numerous in the Miocene. Sus—Pigs Similarly the crowns only of the teeth of pigs below the Crags represent two species, the larger Sus erymanthius, if correctly determined, is a lower Pliocene species but S. antiquus has also been used for these teeth. Incomplete large upper canines which probably belong to this species are unlike those of recent pigs having on the outer surface thick ridged enamel, these ridges on the lower functional canines, kept razor sharp by friction with the Upper canines evidently formed a saw-like edge making them extremely formidable weapons; the canines of our recent pigs which lack this thick enamel are very effective also. The smaller S. palceochoerus, is a Miocene species of which a small metatarsal was figured by Newton but not recognised (plate 3, figure 16, of his Pliocene Vertebrata). This unique specimen is in Ipswich Museum together with an imperfect outer metatarsal of which there is no history, the first specimen was discovered at Falkenham and was in the collection of Major Moor of Bealings. Molars and premolars of both species are represented. The very remarkable canines appear to have escaped the attention of the various palaeontologists who originally described so many sub-Crag fossils. There are two in the Yorkshire Museum and one in the British Museum, at Ipswich there is a portion of a larger canine with similarly grooved enamel which is probably part of a lower canine, it was rescued from a box of unsorted small fossils. Remains of pigs are conspicuously rare in East Anglian upper Pleistocene deposits but the Cromerian Forest Bed has yielded teeth, etc., including the remarkably good skull of S. scrofa in the Norwich Castle Museum, this proving that the geological history of the wild boar goes back at least half-a-million years. Carnivores The Basement Bed has produced very few fossils of Carnivores and the most interesting is the first lower molar of a leopard from the large pit at Newbourne, from which many fossils must have been obtained but unfortunately there seems to be no record. This unique tooth was described by Sir R'd Owen who named it Felis pardoides. The specimen was one of the earliest discoveries for in 1839 William Colchester, of Ipswich, drew the attention of Sir Charles Lyell to the tooth; the pit at that time belonged to a Mr. Wolton. The record does not State that this fossil was taken from the Basement Bed and Owen assumed that it came from one of the numerous "fissures" in the Crag of this site, some penetrating to thirty feet. While this is a possibility, the condition of
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the fossil implies that its origin was sub-Crag. Another tooth, a pre-molar in precisely similar condition, was noticed by the writer in a collection of un-named specimens, it is possible that this is the tooth said to have been found in a pit five miles from Newbourne but which was not described*. DĂźring 1959 half of a third tooth of this species, another pM 4 , was discovered in the Norwich Crag Sands at Easton Bavents by Lord Cranbrook. This is in the British Museum, the others are at Ipswich. The tooth in the Fitch collection at Norwich which is the only feline carnassial tooth from the Norwich Crag of Thorpe and was thought to belong to F. pardoides, was considered by Newton to possibly belong to a "sabre-toothed" cat, Machairodus. Machairodus does not appear to be represented in or below the Red Crag although the genus appeared in the Miocene, one bone in the Manchester Museum associated with Anancus arvernensis from Dove Holesf proves its presence in the Pliocene. In addition to Mr. Fitch's tooth there is one other Norwich Crag record from Covehithe in Suffolk, the middle portion of a canine minutely serrated on both edges, the serrations on the anterior edge worn away and their former presence indicated by a row of minute dots which represent the spaces between. The specimen is in an unusual fossil condition and much less mineralised than most other teeth from Norwich Crag, the enamel has a yellowish tint with black staining. The wear on the leading edge of the canine is indicative of an aged beast which may have lost the tip of the tooth while still living, and may have had some abnormality in the lower dentition which caused the unusual wear. It appears to be the left upper canine. There are some canines from the Norfolk coast deposits which have been recorded as from the Forest Bed (FIG. 30). Some in the finest possible condition are obviously of the same species which is Machairodus cf. crenatidens (there seems to have been some indecision regarding the determination of these teeth in the past but as this species is thought by some authorities not to be distinct from the former M. latidens Owen, M. crenatidens Fabrini has been adopted). Some Norfolk coast specimens differ in their fossil condition and are of the "Black Bones" type and since bones of * Trans. Suffolk Nat. Soc. Vol. 11, p. 238, 1960. t T h e Machairodus canines from Dove Holes, recently examined, have proved to be of the same minutely serrated type as those f r o m the Norwich Crag and Forest Bed. T h e r e are also two upper cheek teeth, poorly preserved, and part of one or two limb bones. As these are associated with bones of Early Pleistocene Cervidae, Dama nesti nesti and Euctenoceros spp-, also elephant and horse, they cannot now be regarded as Pliocene but most probably belong to the Earliest Pleistocene, possibly pre-Red Crag.
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Canine of Machaerodus cf. crenatidens.
this type are not uncommon in the Norwich Crag and Westleton Beds, it is considered they were either eroded from the Weybourne Crag by recent marine erosion and not actually collected from the Forest Bed, or were derived from the Crag in an earlier age. The Machairodus canines from the Upper Pleistocene deposits of Kents Cavern are larger than those from the Lower Pleistocene but the serrations on the edges are rounded and bead-like, they also are very well preserved. They may be specifically distinct. Geological science is indebted to the two brothers David and Peter Long, formerly of Pakefield, for the discovery of the Covehithe Machairodus tooth and for other new records during their residence in the district. T h e hyaena is represented amongst the sub-Red Crag fauna by the teeth identified as H. striata. Professor Lankester had first
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Right m a n d i b l e of Machaerodus
cf. crenatidens Collection.
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originally in t h e Backhouse
assumed two pre-molars from Felixstowe to be a new species, H. antiqua and another tooth from Woodbridge was also referred to this species. Lydekker, however, found these teeth so closely resemble those of the existing North African and Southern Asiatic species, H. striata that there was no reason to regard them as a distinct species. He figured a right upper carnassial from Trimley which is in the Ipswich Museum, there is another carnassial from the left side in the Reed Collection at York. It is unfortunate that most of the teeth of the Crag hyaenas are in the Yorkshire Museum so far away from the region where they should be available for study by visiting specialists; the former Baker and Backhouse collections are also at York. On the continent the species is recorded from the Pliocene of the Val d'Arno, it would appear that the striped hyaena teeth were derived from deposits of the pre-Coralline Crag terrestial phase of the Pliocene. The spotted hyaena, now known as Crocuta crocuta, has no record from Red Crag but is represented in the Cromer Forest Bed Series and seems to have appeared during the later interglacial periods of the Upper Pleistocene. It certainly lived in the Gipping Valley in the latter part of the Ipswichian, its present habitat is south of the Sahara. The teeth in the Reed Collection at York figured by Newton as wolf, Canis lupus, were long regarded with suspicion and when at last there was an opportunity to examine the specimens the doubt was confirmed. The fossil condition was unlike any other teeth from any Crag bed, in fact one was in every way comparable with a tooth of a dog from a mediaeval midden. At least one of the supposed wolf teeth came from Boyton where the basal bed
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of the Red Crag was worked below the marsh deposits and to judge from the condition of this tooth it most probably came from these post-glacialbeds. These teethwereborrowed and testedat the British Museum (Natural History), as expected they are all of recent origin. The remarkable palate of a fox, Canis vulpes, from Boyton, with an almost complete dentition is entirely impregnated with Limonite (hydrated oxide of iron), a Compound of which there is a superabundance in the Red Crag. This fossil condition is unusual for Red Crag but it occurs in the Suffolk Norwich Crag in the Southwold area where a portion of antler in which the bone was completely replaced with Limonite has been found. Anent the apparent rarity of fox remains in the Crag Series they are rare also in the Upper Pleistocene deposits. A new discovery made by T. H. Gardner has been brought to the attention of the writer, it is the posterior portion of a small carnivore mandible, one-and-a-half molars are preserved, the second and part of the first; the posterior portion of the ascending ramus, the inferior border and the whole of the anterior half of the jawbone are missing. Presumably the fossil was broken during a fall of part of Easton Bavents clifF and Mr. Gardner's fossil remained in situ in one of the shell beds. It is referred to Canis vulpes {Vulpes vulgaris) and the condition of this fossil slightly differs from most of the Norwich Crag bones in lacking any notable degree of mineralisation, the exterior is stained dark glossy brown and the interior is soft and friable and is the reason it was so readily broken. Its condition is not surprising since fossil bones from Norwich Crag and the Westleton Beds have one thing in common (apart from the similar fauna), i.e., the very variable fossil condition*. Only one other fossil of the fox has been previously recorded and that from the Red Crag. Amongst the rarer sub-Crag fossils are the teeth of bear. The first record, a right first upper molar from Newbourne in the Colchester Collection, was seen by Lyell who confirmed its origin in the Red Crag, probably the Basement Bed. Owen, who recorded the specimen, thought it was derived from the Miocene, but probably he really meant Pliocene. Beyond remarking that •Mr. Gardner's finds during the current month of June, 1970, include the incomplete femur of a bird (unfortunately indeterminate), and an exceptionately fine third lower molar of the Crag Elephant, Archidiskodon meridionalis, in fact undoubtedly the finest so far discovered. T h e fossil condition of this tooth, like some Mastodon teeth, is very similar to fossil teeth from below the Red Crag. Information has been received that someone was noticed carrying the anterior portion of an ?elephant tusk away from the Cliffs and he probably has other unrecorded fossils, some possibly of unusual interest. It is regrettable that these cannot be recorded at present.
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the tooth was smaller than one from the 'cave bear' it was not referred to any species. The tooth eventually came into the possession of the Reverend Ed. Moor of Gt. Bealings and the collection passed to his son Major E. C. Moor and finally went to Ipswich Museum. There was some confusion during the lifetime of Major Moor because there was another Major Moore who lived at Woodbridge and had similar interests whose collection went to Ipswich also. Newton doubted the determination but evidently examined another tooth, apparently of a pig, and missed the tooth in the collection attributed to Ursus arvernensisl. There is also half of another bear molar. An unfamiliar incomplete bone found during Moir's excavations at Bramford eventually was identified as the tibia of a bear and a few years ago a member of the newly formed Ipswich Geological Group found a portion of a large canine during a Group examination of the lower part of the Red Crag Sands which closely resembles the canine of a bear and lacks the heavy mineralisation of sub-Crag bones, it may therefore be regarded as an indigenous fossil. The Bramford Pit sections have been ruined by gravel digging Operations but other features have been revealed which will be discussed later. The investigation by Cautley and Falconer of the mammaliferous deposits of the Siwalik Hills in far off India revealed the remains of a great variety of animals. Among these was a member of the bear family, Hyaenarctos sivalettsis. The presence of teeth of this creature in the Basement Bed of the Red Crag having been derived from pre-Coralline Crag Pliocene deposits implies that the British Isles were at that time part of a Continental land mass extending eastward to Asia. The genus is represented in Europe and in America. Apart from a molar at Ipswich most of the Hyaenarctos teeth, including canines, are in the Yorkshire Museum. Another Asiatic mammal, the panda, is represented in the subCrag basal bed by an incomplete mandible with one tooth, from Felixstowe, a less well preserved 'toothless' specimen from the Woodbridge area and a tooth from Butley. The teeth are precisely similar in shape to those of the living north-east Himalayan Ailurus fulgens which is about the size of a cat, but the Crag teeth are about one-and-a-half times larger. Boyd Dawkins, who determined these fossils, named them Ailurus anglia. The mandibles, which are exceptionally heavily mineralised, have been subjected to considerable rolling and it is thanks to the early thorough mineralisation that they are so well preserved. The fossils were only examined recently during a visit to York when the important Reed Collection was found stored in boxes thickly coated with the dust of many years. A. fulgens feeds chiefly on fruits, etc., mainly in the mornings and evenings, sleeping during the day and sometimes curled up like a cat.
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Otters are included in the Crag faunas but there is doubt regarding their presence during the Red Crag phase of the Series. A mandible with the carnassial tooth was obtained from the basal bed of the Red Crag of Foxhall; it is in the Moor Collection and was referred to Lutra dubia Blainville, a Miocene species. Later the nomenclature was altered to Pannonictis pilgrimi Kormos. (Dr. Pilgrim was formerly in Charge of the Fossil Mammal Department in the British Museum.) It is believed the specimen has again suffered a change of name but the reference has not been seen. To judge by the condition of the fossil it may well have been derived from the Miocene. Some Lutrine toothless mandibles have been obtained from the Norwich Crag of Easton Bavents, they are smaller than the sub-Crag jaw, and there are two examples of the humerus lacking the proximal and distal ends. These are determined as Lutra vulgaris since they resemble the living species. From the Norwich Crag of Bramerton, Norfolk, a carnassial tooth was discovered which resembles the same tooth of the Indian clawless otter. Newton created a new species based on this tooth, L. reevi, after a former Curator of Norwich Museum, however, there is a fossil Lutrine with the same type of teeth described by Lydekker as L. hessica, a Pliocene species from Germany.
Equus—Horses Remains of Crag horses from the Red Crag are not very common but the fact that there are more from Norwich Crag is largely due to marine erosion of coastal outcrops and temporary excavations. So far the best relic of the large Crag horse, Equus robustus, is from Easton Cliffs and is probably due to a fall of cliff which broke up, if not an entire skull at least the greater part of one. The specimen preserved in Ipswich Museum consists of a set of lower cheek teeth, lacking the third pre-molar, and a few fragments of the mandible, odd detached lower teeth occur with some frequency. There is also, presumably from the same skull, the left pre-maxillary with two incisors, the only incisors of this species known from East Anglian strata. This species is much better represented from the Cromerian Forest Beds but it is very uncertain as to how many bones may have been derived from the Weybourne Crag. In the recent examination of the Savin Collection in the British Museum (Natural History), a number of horse bones from this formation have been detected among the Forest Bed specimens. There are also some "Black Bones" specimens which may have been originally deposited in Weybourne Crag. In the collection there are one or two mandibles of exceptionally large size, also some limb bones referable to E. robustus.
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The upper teeth of horses seem to be less common and many in collections are labelled E. fossilis. Originally in the determination of the smaller Equine teeth no detectable difference could be found between the Forest Bed specimens and those of recent horses, but it was considered there ought to have been because of their geological age, it was therefore proposed that they should be known as E. caballus fossilis. In actual fact the geological age is not very great, probably half-a-million years which is not much considering the evolutionary history of Mammals dates back some two hundred million years. Animals having adapted to climatic and environmental conditions do not change while the conditions remain more or less stable. With any major alteration in the conditions over a period of time the animals either adapt or become extinct. For instance, if the British Isles were separated from the continent towards the close of the Cromerian interglacial, as the icesheets spread southward the fauna would normally migrate southward and living space would become gradually reduced and the fauna would die off. When later the ice had retreated, new contact with the continent would enable a new fauna to become established and some surviving members of the earlier fauna might return. With the oncoming of the Cromerian Glaciation, Mindel I, the south European Vilafranchian fauna became extinct, including E. robustus, but the Caballine horses survived. Remains of horses in any Stratum are indicative of grassy plains. Hipparion, the "three-toed horse", is a Pliocene member of the Equine family tree which is represented in the Crag Basement Beds by rather worn-looking teeth which have been referred to H. gracile. Members of this family are known from the Upper Miocene and Lower Pliocene on the continent. Complete skeletons have been found in ancient lake muds below Lignite Beds (brown coal) near Darmstat in Germany. Rodents
Amongst the rarer Pleistocene Crag mammals is Hystrix sp., the porcupine. The stump of a tooth from an aged animal was among the few mammalian remains from the Bramford Red Crag and for years it was assumed to belong to a beaver. There was, however, something about it which aroused a suspicion that it was not a beaver tooth but although other opinions were obtained it was not until there was a visit of Dr. Miklos Kretzoi that the suspicion was substantiated. Another tooth from an animal of seemingly identical age and the same fossil condition, which is recorded as having been found at Felixstowe, is in the British Museum (Natural History). The distance between these two discovery sites precludes an assumption that they belonged to the same animal, but if there were two porcupines in the area of
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advanced age it argues for very favourable conditions for the species. Porcupines appear to have originated during the Eocene and are represented in the Oligocene, Miocene, Pliocene, and Pleistocene, they occur today in southern Europe, north and west Africa, and southern Asia. The beaver, Castor fiber, is known to be a member of the indigenous Red Crag fauna thanks to the discovery of a tooth in the shelly Crag Sand at Beggar's Hollow, Clapgate Lane, Ipswich, by a member of the Ipswich Geological Group a few years ago: it was taken from two to three feet above the Basement Bed. (This richly fossiliferous site has unfortunately been obliterated.) One other vertebrate fossil has been obtained from this site, an ungual phalanx probably of a bird. Beavers are better represented in the Norwich Crag and the Forest Bed Series and there are both giant and smaller species. These are referred to another genus Trogontherium cuvieri and T. minus. The incisor teeth of this genus has rounded and slightly roughened enamel compared with the flattened and smooth enamel of Castor. T. cuvieri has not been recorded from Red Crag but only from Norwich and Weybourne Crags and the Forest Beds. T. minus was so named by Newton because of the small size of a maxilla with three teeth from Red Crag at Felixstowe, it has been recorded from Sizewell and Easton Bavents, Norwich Crag. The former specimen is at Ipswich. Castor veterior was named by Lankester for two upper cheek teeth and an incisor from the Red Crag of Sutton at that time in the Whincopp Collection, but now at York. Other teeth of this species, originally in the Canham and Moor Collections are now at Ipswich, they are two cheek teeth and an upper pre-molar, all are pre-Crag and known only from the Basement Bed and may be derived from the Pliocene. Hare Lepus cuniculus was recorded by the brothers Alfred and Robert Bell in their Crag mammal list but it is not known on what this record was based. An incomplete incisor similar to a lower incisor of a rabbit is known from Butley. A tooth of Prolagus, identified by Dr. Kretzoi, was found in the Red Crag at Alderton by R. A. D. Markham. It is only seven millimeters long and rather rounded by water action which is not surprising considering it was derived from the Miocene, or the Lower Pliocene and, was not in the basal bed which implies further deposition and redeposition. The Squirrell, Sciurus vulgaris, is assumed to be present during the Forest Bed stage of the Early Pleistocene because of the number of characteristically gnawed fir cones. As the genus ap-
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peared in the Miocene its representatives probably were present in the intervening epochs but it is not to be expected that any remains would be found in Crag Sands: however, these sands are fßll of the unexpected. Hinton, Monograph of the Voles and Lemmings 1926, records Mimomys pliocenicus, M. reidi, and M. newtoni from Norwich Crag, Weybourne Crag, M. intermedius and M. savini from shelly crag at East Runton and more species of Mimomys, Pitymys, and Microtus from West Runton. Other small rodents recorded from the Forest Bed Series are: Arvicola amphibius, A. arvalis, A. gregalis, A. glareolis, and A. intermedius, also Mtis sylvaticus. Large numbers of teeth of these small mammals have been collected from various Cromerian Beds and are preserved in the Norwich and British Museums. Similar teeth have also been collected from the Norwich Crag of Easton Bavents cliffs by Mr. R. A. Long (Trans. Suffolk Nat. Soc. Vol. 8, p. 155, 1953), it is the earliest geological record of the family. Insectivores Remains of the Russian desman, Myogale moschata have been found in the Forest Beds and include bones and jaws with teeth. Other genera include the mole, Talpa europea; the shrew, Sorex vulgaris and 5. pygmaeus. These have not been recorded from any Crag Sands. The geological history of the moles and shrews date from the Miocene, family histories of twenty-five million years. THE CRAG SANDS The Red Crag The marine sands known as the Red Crag are contained in a limited area from Walton-on-the-Naze more or less along the Stour Valley inland to Cläre in the south and to the Aide Valley to the north. At least that is what has been mapped and the western limit was shown at Bramford on the geological maps, though in fairness it must be stated that no deposit can be mapped if there are no surface indications. Recent borings have shown, however, that the Red Crag does exist outside these limits in Suffolk and there is perhaps the possibility that the north Essex limits may yet be extended. The bores at Benhall, north of the Aide, G.R. 259613, and at Jacks Green, Creeting St. Mary, in the Gipping Valley, G.R. 094560, proved that typical Red Crag does occur beyond the mapped limits. The Crag at these sites, like the lower part of that deposit in Walton Cliff, is grey and it is possible that the grey Crag in the Sizewell bores may also belong and any new bores for an extension of the power Station must be checked for fossil evidence to confirm this or prove otherwise.
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Details of the Benhall and Creeting bores were given in these Contributions, Part 3. The beach deposit of the Red Crag Sea outcropping in the Hascot Hill Valley between Barking and Battisford is deteriorating due in part to indiscriminate digging by geological parties and partly to the natural formation of talus; there is also some dumping of refuse. This is a site of Special Scientific Interest and should be protected. Düring a recent visit it was found that a new excavation had been opened on the opposite side of the road where the pebble bed was thinner and with sands above which appear to belong to the Crag and not glacial outwash from the overlying tili. To the west of Battisford, well bore records indicate probable Crag sands below 100 feet of Lowestoft Till. At Barking the ten feet of gravel on eight feet of "silver" sand below sixty feet of tili is probably the Crag Beach and Creeting White Sand. A bore at Moats Tye, Coombs, records ninety feet of tili above fifteen feet of brown sand and gravel over ten feet of sand and shells which can only be Crag and the brown sand above could well represent the Battisford beach as they occur at about the same level. A well bore which penetrated to a depth of over 500 feet was made at Roaneoak Farm, Debenham*, which is situated at 190 feet O.D., the log record follows:— Gipping Till Lowestoft Till PGlacial sand PDecaicified Crag Crag Crag Red ?Crag Crag
Yellow clay Blue clay Yellow sand Fine brown sand Grey sand Black sand Shelly sand Chalk, sand, and shells Chalk to
6' 50' 10£' 20}' 28' 20}' 1654' 52' 166'
56' 66$' 86}' 114}' 13 5 J ' 301' 353' 519'
To comment on this record of the mid-Suffolk underground it has already been mentioned that Gipping Till is sometimes yellowish from the amount of loess the Gipping ice picked up but the Lowestoft Till can be blue (see Part 3 of these Contributions). Yellow sand occurs immediately below the Lowestoft Till in many places but it is not universal. Decalcified Red Crag is invariably brown though grey is typical of this deposit at depths unaffected by weathering influences. Large patches of the Crag are black owing to the presence of manganese dioxide but no such black Stratum has been observed at any outcrop. However, it is not possible to observe the geological conditions at depths of a 100 feet or more and without samples it is impossible to estimate what the black Stratum may be if not Crag. Well borers are not trained in geological terms and their records are often very difficult to interpret. • T h i s name does not appear on recent maps, it may refer to Oaktree Farm.
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Two other bores in the Debenham district at Kenton Rectory and the Eastern Counties Farmer's property are also significant; they are given under a. and b. below:— a. G i p p i n g T i l l 10' Lowestoft T i l l 72' G r e y sand 110' Shellsandstones 107' Crag 117 feet. O . D . 171
82' 192' 299'
b. G i p p i n g T i l l L o w e s t o f t Till Shells and sand C r a g 167 feet.
10' 58' 167'
O.D. unknown
Base of Crag twenty-eight feet below O.D. in bore a. and if the sites are about the same elevation there would be a greater amount of Crag below sea level. The 165 feet of shelly sand cannot be anything but Red Crag because the Norwich Crag is not uniformly mollusciferous, the shells occur in layers in otherwise unfossiliferous sand, gravel or clay. This is a phenomenal depth for Red Crag, 300 feet but it occurs within the ränge for the whole Crag Series, which is minus 170 feet at Southwold, plus 150 feet for the Battisford Crag Beach. In Norfolk the Norwich Crag is said to occur at about 150 feet 0.D. also. It is appropriate to record here that recent borings below the Orford Ness Shingle Spit have revealed thirty feet of reddish Red Crag two miles or more from the nearest outcrop. It has not been possible to determine if this Crag was redeposited as the colour implies, but the number of whole shells seems to be against this. One would have expected that Crag Sand permanently below water level to have been grey or perhaps greenish. The chalk, sand, and shells may perhaps be an indication of a chalk cliff, or outcrop suffering erosion by the Crag Sea. It is difficult otherwise to account for such a mixture. The base level of a Red Crag deposit at 350 feet below the 190 foot contour O.D. is remarkably exceptional; it is 160 feet below the present sea level and could represent the silting up of a preCrag canyon or Valley. Red Crag at this level would be much older than the supposed earliest deposit of the Early Pleistocene Crag at Walton -on-Naze and proof of a very much lower sea level, which would be expected if there had been a pre-Crag glaciation. At Hill Farm, in the same parish and the same height above sea level, the surface of the chalk is about 150 feet higher, no shelly sand is recorded; the depth of the grey sand is about the same, 1.e., twenty-nine feet. Above this bed ten-and-a-half feet of gravel lies below twenty feet of "Silver Sand"; there is no brown sand but fifteen-and-a-half feet of yellow sand and gravel occurs below the Lowestoft Till and fifteen feet of Gipping Till. Evidently there is an abnormal hollow in the surface of the chalk. The Debenham "Silver Sand" may represent the Creeting White Sand which occurs at about the same level at Creeting St. Mary where it has been established as one of the Crag Series.
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Chapel Farm, Earl Stonham, marks another site where hidden Crag has been detected from a bore log. The Farm is 150 feet O.D. PGipping Till Lowestoft Till Glacial sand and gravel G r e e n running sand Dark green sand Crag Flints and sand Chalkto
Light brown clay Boulder clay Sand and gravel
15' 35' 25' 36' 15' 40' 1' 67'
50' 75' 111' 126' 166' 167' 234'
Ninety-one feet of Crag, with sixteen feet below present sea level. Two other bores in the parish have seventy-five and eightyfour feet of Crag, one having shells in the green sand; another has thirty-eight feet of shelly green sand in fifty-seven feet of Crag and two more, at College Farm and Forward Green, have eightyfour feet of Crag. In northern Suffolk green and grey Crag, with and without shells, occurs in bores at South Elmham St. James and St. Cross. The deposits are 109, 81, and 66 feet. Normally Norwich Crag would be expected this far to the north but an iron cemented Crag with Neptunea contraria occurs on the chalk of the Norfolk coast near Cromer which is very like the Suffolk Red Crag. To the west of Stowmarket at Bridge Farm, Great Finborough, there is eighty-five feet of Crag below the Gipping and Lowestoft Tills, and at Finningham there is forty-seven feet of grey Crag and grey sand. The well at Glevering Hall was bored through sixty-three feet of Crag lying below sixty feet of glacial deposits. Below sixty feet of tili at Haughley Green there is twenty feet of dark green sand, thirteen feet of black sand, five feet of green Crag with stones, and another thirteen feet of green sand on chalk. Harleston Green the elevation is 210 feet O.D. and in a well bored to a depth of 250 feet, the bottom twenty-three feet are grey Crag below 140 feet of glacial tills and outwash deposits. The area around Henham is pebbly gravel and sand of the Westleton Beds and Norwich Crag, so far as can be seen from surface exposures, but the thickness of the Westleton Beds below the Park is sixty-nine feet; below this there are seventy-seven feet of Crag deposits mainly green. Further up the Blyth Valley at Holton Hill Farm, below the level where the large Gravel Pit is worked and under the marsh deposits, there is the following sequence:— Sand and gravel Red sand Grey sand and shells
2' 25' 5'
27' 32'
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Soft clay Grey sand and shells Grey, blue, brown clay Grey sand and clay Hard clay Chalk and fiints
5' 5' 25' 15' 15' 165'
37' 42' 67' 82' 97' 262'
In Norman's Gravel Pit, twenty to thirty feet below the water table, there is a grey zone with shells which is cemented with Pyrites or another iron sulphide, Marcasite. In addition the shells, bones, and teeth of the Villafranchian fauna of the Crag Series are associated with abundant driftwood and erratic pieces of coal and nodules of Clay Ironstone such as occur in the Coal Measures. It would be interesting to know if the pyritised zone is higher than the uppermost grey Stratum in the bore or if it is equivalent to it. The pyritisation could be a very local phenomenon like the two places where Red Crag had become solidified with crystaline Calcite. Horham, a village five miles from Eye, to the south-east and supposedly well outside the Crag area has a deep bore at Thickthorn Farm, situated near the former Railway Station at 175 O.D. Gipping Till 10' Lowestoft Till 60' 70' Sand and pebbles 40' 110' Grey blowing sand 30' 140' Dark sand and silt 30' 170' Sand and shells 62' 232' Grey silt 5' 237' Grey hard sand 18' 255' Grey clay 22' 277' Grey hard sand 22' 299' "Crag" I Z 12' 311' Sand, stones, and silt 2J' 331J' Chalk to 1 I'' 76' 407f There are 179 feet of Crag deposits below 110 feet of glacial deposits and again we have Crag deposits resting on chalk at an abnormal level no less than 146 feet below the North Sea. Could this be part of a buried Channel extending eastward to Debenham? About half-way between Hoxne and Stradbroke there appears to be 150 feet of deposits of Crag age at Corner Farm (Chickering). Here again the base on chalk is well below the present sea level, namely 194 feet. T h e site is 150 feet O.D. At Oakley Park, about 140 O.D., a bore log of 1877 records sixty-seven feet of ligin green Crag below twenty-five feet of "beach-like shingle and sand", there is seven feet of clay between the Crag base and the chalk at nil feet O.D. Another log of the same year relating to Hoxne Rectory, at an estimated elevation of 100 feet, records seventeen feet of loose sand and Crag above sixty feet of sand with Purpura lapillus. This mollusc must have been abundant enough to cause comment and it is normally very common in Red Crag.
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The Crag base, on ten feet of clay is at 152 feet O.D., about fifty below the surface of the North Sea. A bore at the Hall, Ilketshall St. John, situated near the 100 foot contour provides another record of the curious mixture of sand, chalk, and shells, the section follows:— Gipping Till Gravel and sand Gravel Grey sand Shells Flints Chalk, grey sand, shells Chalk to
19' 59' 1(T 35' 23' H' 67' 21'
78' SUT 123' 146' 147J; 214' 235'
At this site there is 269 feet of presumed Crag deposits with the curious mixture of chalk, sand, and shells, the thickness of which implies a long period of erosion of a chalk outcrop or cliff. This phenomenon has previously been noted in the Debenham section and the evidence for a Channel extending south-west from the area of Lowestoft towards Stowmarket is very strong. There is further evidence provided by a bore at an unspecified site at Rattlesden, four miles west of Stowmarket, where the channel is less deep or perhaps the boring was made toward one side. Underneath 124 feet of tili and thirty-six feet of ballast there is thirty-nine feet of brown, green, and shelly sands, the base of the Crag about fiftynine feet below sea level. The boring at the Hall, Redlingfield, is unusual with fifty-one feet of blue clay and sand below the Crag which is 139 feet thick, the füll record follows:— Gipping Till Lowestoft Till Gravel Greenish grey sand Grey sand Sand and shells Blue clay and sand Chalk and grey sand Chalk to
4' 52J' 6' 70' 39' 30' 51' 55' 89'
56$ 62' 132' 171' 20r 252' 302' 391'
Seventy feet of grey sand and seventeen feet of shelly sand represent the Crag at Redisham about four miles south of Beccles, below these, is an unspecified thickness of mixed sand, chalk, and shells. At this site the base of the Crag is in excess of thirty feet below the Ordnance Datum. Ilketshall and Redisham are about four miles apart and the hollow in the surface of the chalk is considerable, from this it may be inferred that it must be at least half as wide again.
335
GEOLOGICAL HISTORY
Four miles west of Stowmarket, at Rattlesden, there is thirtynine feet of brown, green, and shelly Crag below 160 feet of glacial beds. Here the base of the Crag Sands are forty feet above present sea level. Further to the west at Pakenham, four-and-ahalf miles north-east of Bury St. Edmunds, a boring at Hall Farm records below seventy-two feet of glacial beds, green sand six-anda-half feet, green sand with pebbles six-and-a-half feet, grey sand with pebbles four-and-a-half feet, live grey sand seven feet, and five feet of grey sand with layers of clay. The base of this series is forty-two feet below O.D. and the most westerly record of presumed Crag Sands of which notes are at hand. The compilation of a partial index of well bore records has enabled an estimation to be made of the underground structure over much of the county, also the presence or absence of members of the normal sequence of geological strata is made known. In the area of the abnormal hollow in the surface of the chalk, the records show the complete absence not only of the London Clay but the other Lower London Tertiaries which are known to be present in south-east Norfolk and at Lowestoft. The geologically important bore of the former Ice Company at Lowestoft made in 1832 is given below:— Drift—(Glacial deposits) •Chillesford Beds = (Forest Bed) "Norwich C r a g " London Clay Reading Beds (475' to surface of the Chalk) Chalk Upper green sand Gault Lower green sand Rock—(PSilurian Limestone)
69 i ' 4|' 166' 160' 75' 1,055' 11' 45' 41' 205'
2,102'
Limestone penetrated in the Harwich and Weeley, Essex, deep bores belongs to the Palaeozoic platform, which appears to be elevated below East Anglia, has been thought to possibly be Silurian, or Lower Carboniferous. The bedding of this rock has been subjected to folding such as occurs in the formation of mountains and is highly inclined in the bore core exhibited in Ipswich Museum. The Red Crag is variable and is dark reddish passing into brown or yellowish, black patches are generally due to Manganese dioxide and lenticles of white sand occur. The removal of shells (decalcification) by percolating acid water changes the colour of the Crag to a darkish brown. In the decalcified zone hollow moulds of shells sometimes occur and prove the former mollusciferous character of the sand and its relationship to the shelly Crag beneath. Some areas have mainly shell fragments closely packed together forming a hard mass with few entire shells, notably at Buckanay
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Farm, Alderton. At Bawdsey Cliff, and elsewhere, the bedding is variable with numerous thin, iron impregnated layers which were originally silty, but in general the sand is loose enough to be affected by wind erosion. There are places like the Priory Pit at Butley where numerous vertical stalactitic concretions occur with impressions of shells. This pit was unused for a number of years but in recent years it has been cut back further into the plateau and deepened and appears to be less rieh in shells. The large currently worked pit on Waldringfield Heath is very rieh in iron and not particularly rieh in shells except at the water table and below. A small pit near Vale Farm, Shottisham, has the minute Echinoderm, Echinocyamus pucillius, and is reasonably shelly. Another pit near Alderton House has the small Sea urchin in large numbers, which are best sought on the talus. The tests are about one-quarter of an inch in length. Echinocyamus pucillius occurs in the Waltonian Red Crag and has been recorded from the Pliocene Coralline Crag where it seems to be rare. One speeimen was found in a sample from the bore at Jack's Green, Creeting St. Mary. The Crag from this site, which is presumably in a hollow in the chalk, is grey. There is no indication of this grey and normally shelly Crag in the various large excavations in Broom Hill. At the south end where the surface of the chalk has been exposed by the removal of the Creeting White Sand the basal bed has a resemblance to the Basement Bed of the Red Crag with occasional rolled pieces of Cetacean bone. Under the auspices of the Nature Conservancy an inspection of Crag sites was made in 1953-54, the list of pits then open appears as Appendix 2, para. 4 at the end of this Contribution. The lower part of the Red Crag over most of the area has highly inclined bedding, this can be seen at the small exposure on the opposite corner from Virtue's Farm, Hollesley. (This site has little value for palaeontologists.) DĂźring 1953 this inclined bedding zone was exposed in a trench from Belstead Lodge to Stone Lodge, Ipswich, a distance of three-quarters of a mile and in this section the Crag Sand was very sparcely fossiliferous whereas the old stackyard pit at Gusford Hall was reasonably shelly. This is now the site of a school.* The upper part of the inclined zone has the appearance of having been uniformly planed off and the bedding above lacks the earlier uniformity. Much of the upper zone has indications of having been redeposited with mainly fragmentary shells as would be expected from the cross bedded nature of this zone, which *Trenches for a new housing estate nearby exposed another outlier of the Oldhaven Sand previously recorded at Hoghighland, Cliff Quay, and Bobbitshole.
GEOLOGICAL HISTORY
337
originated in deposition by changing currents. These sometimes laid down sands of different grades and colours which were richer or poorer in molluscan remains. Bivalve molluscs by reason of havxng two shells for each individual give the impression of being more common compared with the tests of univalves, indeed there are places where in fact this is true. T h e bivalve tests invariably lie convex side upward. T h e molluscan fauna varies from area to area, in one place shells of Mya arenaria are abundant, but unfortunately are usually cracked and entire specimens rare. In other parts of the Red Crag this species is represented by rolled fragments and only the hinge portion is recognisable. In places like Beggar's Hollow, Ipswich, four miles from the nearest Coralline Crag outcrop at Tattingstone, the Red Crag is rieh in derived Polyzoan remains and lt is very probable that some of the more robust shells from the Phocene Crag have also been mixed with the Early Pleistocene molluscan fauna. As many of the same species occur in both Crags, it is most difficult to distinguish the older specimens. At Stratton Hall, six miles south-east of Ipswich, Coralline Crag debris is mixed with Red Crag shells. Red Crag in the vicinity of the Coralline Crag at Sutton and at Newbourne and Waldringfield in particular, has produced a suspicious number of Pliocene species which have been aeeepted as indigenous Red Crag fossils, species which otherwise are poorly represented in the newer Crag. Neptunea contraria, "the left-handed whelk", is particularly abundant at some localities such as Beggar's Hollow* and Piper's Vale, Ipswich, also Walton-on-Naze where the shells of the species are much less robust than the SufFolk specimens. Formerly at Piper's Vale the shells of this species were washed from the Crag by high tides and scattered over the foreshore. Some shells of N. contraria from the Newbournian zone are giants of the species seven or more inches long; in the Butleyan zone, however, the shells are small but no less robust. M u c h sifting of the Crag Sand at Beggar's Hollow for very small species revealed a high mortality among the young of this species, the shells ranged from under a quarter of an inch upward and the fact that the protoconch was still attached, even to many well grown shells, proved that this part of the Crag had not been redeposited. T h e only vertebrate remains from this site were a tooth of beaver and a phalanx, probably of a bird, and there were no derived remains of earlier mammals. * T h i s interesting section has recently been destroyed by the Local Authority in landscaping the refuse tip which has obliterated the former attractive Valley.
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The shells of mussels, Mytilis edulis, occur sporadically throughout the Red Crag but there are concentrations in places. These bivalves normally anchor themselves to stones, rocks or wood piles; it is curious that these fragmentary shells are fairly common in parts of the Crag where there is no evidence of possible anchorage and are very uncommon where they would be expected in the vicinity of blocks of rock on the Crag Sea floor. Winkles, Littorina littorea, appear to be uncommon in the Red Crag and this may be due to unfavourable climatic conditions. They become very common, albeit of small size, to the north of Aldeburgh in the very mollusciferous Norwich Crag sands of the Rifle Range on Sizewell Warren, also at Bramerton in Norfolk. On two occasions exceptionally rieh patches of fossiliferous Red Crag have been observed; one was at Sutton in an overgrown pit, between the Knoll and the River Deben, and consisted of a packed mass of largish shells with little or no sand beneath the exposed roots of a large tree. The other was in a cliff of Red Crag at Ramsholt where there was a very great amount of shell forming a hard mass which was difficult to break. Two other exceptional observations were made of areas of unknown extent exposed in temporary excavations in Red Crag. One was in Speedwell Avenue, Chantry, Ipswich, where the whole of the shelly Crag had been converted into a sandy limestone by the formation of crystaline Calcite (Carbonate of Calcium), the other was at Tattingstone Hall Farm when an excavation was made below the level of the farmyard and the same phenomenon was seen. Occasionally the observer may see a white incrustation in fissures or perhaps somewhat stalactitic forms. This is a calcareous tufa type of deposit resulting from the Solution of shells at a higher level, sometimes from an upper level which has vanished owing to denudation of the landscape. A good example has been visible in the Alderton Pit for some years. Two sites with abnormal Red Crag, more or less grey in colour, have been noted, one at Felixstowe and the other at one of the sections in Beggar's Hollow. In both places the Crag was water-logged and the shells, mostly fragmentary were soft and chalky and evidently partly decomposed. Flints in this deposit were partly Cretitised*, i.e., decomposed. The Crag could be considered as in a porridgelike condition. Some deer bones were obtained from the Felixstowe site. *Flints are generally composed of three crypto-crystaline forms of Quartz, Flint, Chert and Chalcedony in varying proportions, some flints are purer than others. Under certain conditions one of these varieties changes and becomes friable or even a white powder. T h e produet of this decomposition is called "Cretite". Cretitised flints occur in Crag below the water table.
GEOLOGICAL HISTORY
339
The Crag Pits in the Newbournian (middle) zone of the Red Crag were possibly the riebest in fossils and it is unfortunate that all the old ones are overgrown or filled in. The last pit to be worked was near Stratton Hall, Levington. The Crag was put through a rotating screen and the small fragments of shell separated and sold as "shell grit" for chickens up to 1939. The larger and more robust shells were discarded and provided good pickings for visiting geologists. Amongst the molluscan fauna Cardium parkinsoni was fairly common and with luck and much care the rather fragile shells might be extracted: this species is a very large cockle. The shells of the common cockle, C. edule, larger than average were obtainable with ease. Other more fragile members of the genus were represented by incomplete shells were C. decorticatum and C. interruptum. Some of these were rolled and were probably derived from Coralline Crag, like the erratic Polyzoan fragments in the same pit. Another bivalve, Glycimerus (Pectenculus) glyeimerus was particularly abundant and like the Neptuneas at Beggar's Hollow shells representing all ages were present. Shells of the scallop Pecten maximus, were fragmentary and rolled, these were certainlv derived. P. opercularis, an abundant species at Alderton was less common. Cyprina islandica, a fairly common species at Bawdsey was represented by fragments. The large thick shells were frequ'ently unable to resist the weight and pressure from above, this including the incaiculable tons of ice of sundry glaciations. This mollusc was living in the Coralline Crag Seas and is in Norwich Crag shell beds. It is fairly common in the Bawdsey Crag. Other bivalve genera include Astarte spp. and Spisula (Mactra) spp. Shells of the larger S. arcuata, etc., could be Seen in the section but were impossible to extract, they are very thin and exceptionally fragile. Serious collectors who wish to have all possible species represented will need to take imperfect speeimens as it is impossible to obtain entire shells of all kinds, i.e., shells of Glycimerus angusta one would consider strong looking but usually only hinge portions are found. ^ Univalves were well represented, notably N. contraria with many of the shells coated with deep red oxide of iron. Nassa reticosa and many other species of this family, which is a large one, occurred. These shells are fragile and have usually suffered some damage. The species ränge from medium-large down to little more than a quarter inch long. The genus Turritella was represented by well grown speeimens up to maximum size and one was fortunate to obtain more than half a shell. Buccinopsis
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Suffolk Natural History, Vol. 15, Part 4
dalei was fairly common, also various species of the genus Natica, including N. multipunctata. Purpura (Nucella) lapillus was well represented by its varieties, one of which is characteristic of the site, it is a rather inflated looking shell. These shells are rather strong and generally well preserved, they are often encrusted with small barnacles which seldom attach themselves to other species. One other univalve of the genus Sipho, of sundry species, has been found in the Stratton Hall Crag. At Bramford the Crag Sands are thinly bedded at the base and this laminated feature has been observed at Bawdsey and some other sites, they are brownish and pass up into white mainly quartz sand with thin greyish layers of finer grain. Further up the Gipping Valley at Creeting St. Mary there are thick deposits of current bedded white sand with minute flakes of mica (Muscovite). The Creeting White Sands rest on an eroded surface of the chalk which is ironstained. There is a thin basal bed to the white sand, with a scatter of irregularly shaped flints, mostly from the Bullhead Bed which normally forms the basement bed of the Thanet Sands and lies on the surface of the chalk. All these flints have an eroded appearance as though they had at some period been subjected to Cretitisation. They have a brown rusty appearance quite unlike those in the Bullhead Bed where they are a dark green due to the presence of the mineral Glauconite in the Thanet Bed; obviously the Glauconite has been oxidised. Rare bits of subCrag bone occur below the white sand. Glauconite is an earthy, sometimes granular mineral, an hydrous Silicate of iron and potassium, which is believed to have been present in the Red Crag and it is to its oxidation that the colour of the Crag is due. It is commonly found in marine deposits. Glauconite is evidently present in the concealed green Crag Sands recorded in the foregoing bore logs. It may perhaps be assumed that the grey sands contain a lower concentration of Glauconite. Obviously there was none of this mineral in the white sands. The Creeting White Sand has been proved to be of marine origin because of the presence of extremely rare casts of marine mollusca, such as Turritella. The cross current bedding is similar to that in the Red Crag, these features are emphasised by slightly harder very thin layers and in the Red Crag these are impregnated with hydrated oxide of iron. In the Upper part of the White Sand there are numerous minor "faults"; there is every reason to believe the faults were caused by the pressure of Lowestoft ice when the sand was water-logged and frozen solid. Similar faulting has been observed in other deposits and notably in the former Valley Farm Pit, at the Washbrook end of Sproughton parish, where a remarkably good example of double Step faulting was exposed at one time. At this site the lower part of the
GEOLOGICAL HISTORY
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white sand passed down into the normal shelly Crag just above the water table. T h e pit was situated between the 100' and 125' O.D. contours, the depth of the sand was similar and it is the most southerly exposure. Eastward the white sand occurs below Gipping Gravel at Rushmere St. Andrew, at T u d d e n h a m and farthest east at Hollesley where again it rests on shelly Red Crag. T h e clean white sand is not compacted and the sections are readily sculptured by the wind leaving the thin, harder layers projecting. Sometimes the sand dislodged by the wind trickles down in intermittent streams producing interesting fluted formations. T h e Creeting St. Mary Broom Hill is the most important section because it is there where the critical evidence regarding the place of the white sand in East Anglian stratigraphy was demonstrated, the section follows:— Gipping Till. Gipping outwash glacial gravel with similar erractics in both deposits, and Red Crag debris. Lowestoft Till, partly weathered, about 4 feet. Baventian Clay (Chillesford Clay) in the first Geological Survey Memoir, about 2b feet. Greyish gravel with angular and sub-angular flints, chiefly grey in colour, in white sand, with very numerous non-flint siliceous erratics and rounded nodules of vein-quartz. Passing down into:— Creeting White Sand, with plentiful minute flakes of mica which glisten in sunlight. Where the sand occurred immediately below the glacial gravel it was slightly ironstained. The lower tili and Baventian having been lost. Depth about 20 feet. Coarse brown gravel—Basement Bed in Creeting Sand Quarry, ?2 to 3 feet. Upper Chalk, Eastall's Pit at south end of Hill, scattered brown flints with very occasional sub-Crag type pieces of bone. Thickness, a few inches.
Although well aware that the Baventian occurs above the Norwich Crag in the Southwold area it was quite a while before it was realised that the sum of the evidence gave no alternative to the fact that the Creeting White Sand was part of the East Anglian Crag Series. Similar white sand occurs as part of the Westleton Beds, above the pebbles and like that at Creeting has small flakes of mica. At the top of the Westleton shingle at Wangford, a site between Holton and Easton Bavents, there is a remnant of weathered laminated clay which appears to be Baventian. T h e Westleton pebble beds at this site rest on shelly Norwich Crag and the whole deposit is much thinner than at Holton and Reydon, near Southwold. At Holton the working section is about forty feet high and the floor of the great pit only a very few feet above the water table. Formerly the gravel was firstly p u m p e d and later dredged from another twenty feet or more below the surface of the water. T h u s there is at least sixty feet of Westleton Beds
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which have been the subject of controversy since they were first described a Century ago by Joseph Prestwich. It is thanks to the great demand for aggregate with which to make concrete that these richly stony deposits have been opened up on such a large scale making possible more intensive investigation than was possible to earlier generations of geologists. Gradually fresh pieces of the jig-saw are falling into place and as new observations are made further additions can be made towards completing the picture, which for obvious reasons can never be fully completed. From the most southerly exposure of the white sand at Sproughton, above the Washbrook Valley, to Reydon, Southwold, is about thirty miles in a direct line to the north-east, to Hollesley it is fifteen miles to the east and from there to Holton is about twenty miles. Creeting is eight miles north of Sproughton. There are no bore logs to hand of the area within the points given above by means of which it can be determined if other sites in the region have white sand. However, as much of the land to the east of the A.12 is well below the 100 foot contour the white sand would very rapidly be eroded as the plateau level was lowered, and is presumably lost, but the Hollesley site (now a dump for old cars) is not much above the fifty foot level. This is perhaps in accordance with the top of the Westleton Beds at Holton where at least three glaciations have done their bit in reducing the thickness of the deposit. The Westleton Beds—sensu stricto Dr. Richard Hey has worked exclusively on the constituent pebbles of the Westleton Beds, they have been graded for size and the erratic pebbles analysed, but it is contended that the identity of any deposit truely depends on the sum of the observations of observers in a variety of disciplines. Thus it is that a good deal of pertinent data has not been included in his paper on "The Westleton Beds Reconsidered"*. Dßring the earlier stages of gravel digging at Holton, a Channel filled with Lowestoft Till was exposed at the western end, cutting deeply into the shingle. As the section was cut back farther from the road a much smaller Channel through the Upper part of the Westleton Beds was exposed. This appeared to contain Gipping Till. As the section was extended to the east the lower part of a glacially formed Channel with an indeterminate tili was also revealed, it was not typical of any known boulder clay and appeared to be a mixture and it was not possible to identify the particular glaciation concerned. A year or so ago, the section having cut back to the lane parallel to the Southwold Road a mass of tili •Proceedings of the Geologists Assn. 1967, Vol. 78, pp. 427-445.
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generally resembling the Norwich Brickearth was observed to become thicker as the section was worked back into higher ground. Below the base of the brickearth at the lowest point there are thin beds deposited by an undermelt stream of which the lowest part was a calcreted calcareous silt. Sub-glacial stream deposits vary from extremely fine sand to well rounded pebble gravel as has been indicated in many sections in the Gipping Valley, in fact one sub-glacial Channel at Claydon has a brecchia of angular chalk fragments and fine sand. Of course this has nothing to do with the Westleton Beds, but the channelling with different gravels cutting into those beds at Holton and the upper deposits of Easton Bavents cliff appear not to have been recognised as Coming into this category. T h e fact that the Channels have similar suites of pebbles may be accounted for by the stones having been picked up by the first advance of the Cromer Ice (Mindel I, or Elster glaciation) as it passed over areas from which the Westleton Beds have vanished leaving outliers not now connected with the main area. T h e presence of "green lava" similar to that occurring below Norwich Brickearth in Norfolk in these gravels is most significant. T o sum up, the material in these Channels may have Westleton pebbles but they are erratics in their present location and stratigraphically are of a more recent age. Over most of the Westleton Beds, where exposed to any considerable depth, there are generally layers of shingle, one above the other, all dipping seawards at much the same angle that may be seen on recent beaches. One odd feature was noticed very recently at Wangford where pits have been made on each side of the lane, Dr. Hey in his Plate 13A shows the section furthest from the road at Wangford with the bedding planes dipping south-east. T h e opposite section by the ramp leading to the pit floor has no indication of bedding and no sign of deposition in water, many of the pebbles are lying at all kinds of angles and quite a number have the longer axes either vertical or are highly inclined from the horizontal. T h e fact is this particular section resembles in every way a tili composed of gravel, or a deposit which has been deeply frozen causing the displacement of the stones from their original Position. On the same occasion it was discovered there was a mass of tili in a Channel parallel to the lane in the newer pit across the road. It is considered, however, that it was not close enough to have affected the section described. T h e large Holton pit having been longer under Observation has yielded more pertinent material than other sites although all have now produced mammalian remains. Amongst the stones at no particular level small pieces of brittle coal occur and when material was brought up by the grab from below the water table there was a good deal of inferior coal and sizeable nodules of clay-ironstone were fairly common. These were from near the eastern end of
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the excavations where on occasion erratics up to a foot or more were brought up, they were generally angular and could perhaps have been transported by floating ice. One very surprising find was the limb bone of a Jurassic reptile, probably a Plesiosaur. T h e pyritised zone at the lowest submerged level reached has been mentioned. It is important in as much as there were shells in this bed, poorly preserved it is true, they are impossible to extract from the mass. One part of this zone consisted of small pebbles cemented together to form a pyriteous conglomerate without surviving fossils. Also from this level there were quantities of wood all with a sulphurous odour which decomposed forming an efflorescence of sulphate of iron, pine and oak were recognisable. Mammalian remains from this level were in a unique fossil condition, including Libralces gallicus, Euctenoceros sedgwicki, E. falconeri, E. cf. tetraceros, Equus sp. and the Crag elephant, Archidiskodon meridionalis. T h e elephant was a juvenile. Above the water table the bones were very rusty-looking from the amount of ferruginous sand encrusting them and they were quite hard and invariably incomplete, mostly portions of elephant bones. Their condition differed from Norwich Crag bones from the same level in the Norwich Crag of Easton Bavents. Bones from the higher levels were in poorer condition and at the uppermost mammaliferous horizon they are so friable that they may be crumbled in the fingers. Wangford has produced very few bones, the most notable being a nearly complete elephant femur. As the deposit lacks the depth of other sections perhaps this is not surprising. Reydon has yielded mostly bones and teeth of elephants, all from below the water table where there is so far no indication of a pyritised zone. When the grab penetrated to an abnormal depth shells were brought up and since that time imperfect shells have been detected at a higher level. Evidence of shells at a higher horizon at both Holton and Reydon is seen in the harder layers where hollows are preserved from which the shells have been dissolved by percolating water, the reduction of bones to a friable condition was due to the same agency probably long ago before the advent of the post-Crag ice, the tili of which would seal in the very permeable deposits and keep water out. However, in those places where the overlying impervious clay was removed by prolonged denuding agencies the decomposition of fossils would become complete. Naturally this will apply both to the Creeting White Sand and the Westleton Beds. T h e lower part of Covehithe cliff, to the north of Easton Bavents, is composed of a highly contorted brown argillaceous deposit with shells derived from. Norwich Crag included here and there. T h e original surveyors regarded this bed as a northerly extension of the
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Chillesford Beds which overlie the Red Crag marginally around the Sudbourne-Orford Coralline Crag " I s l a n d " and is actually confined to that area. Although other opinions have beeil expressed the preponderance of evidence points to the clay being a southerly extension of the Norwich Brickearth which occurs at the same level, i.e., the foot of the cliffs towards Lowestoft. About twenty years ago a thin brown layer of similar brown clay appeared from below the beach at the north end of Easton Bavents Cliff passing up over the Norwich Crag Sand and the Baventian Clay. As the cliff face has receded owing to attacks by the sea this brown clay has become thicker and has proved to be Norwich Brickearth. T h e foregoing observations indicate that the Red Crag, the overlying Creeting White Sand, the Norwich Crag, and the Westleton marine shingle beach deposits are all older than the Baventian Clay and that the whole ante-dates the advance of northern ice which deposited the Norwich Brickearth. It therefore follows that any accumulation of gravels containing a high proportion of Westleton pebbles in gravels between the Baventian and the Norwich Brickearth represent glacial outwash deposited in advance of the ice front and overridden by the ice. (This phenomenon has been clearly demonstrated in the Gipping Valley, in particular at Broom Hill, Creeting, where Gipping Till may be seen overlying outwash originating from that ice.) There can be no doubt that the cbalk-free brown Norwich Brickearth, which has puzzled generations of geologists because of the absence of chalk from this tili, owes its unusual character to the fact that the ice having passed over a large tract of Norwich Crag is largely composed of that material. T h e gravel-filled C h a n n e l s cutting into the upper part of the Westleton Beds and the Norwich Crag of the Easton cliffs, appear to be due to streams of glacial melt water, the partial overlapping of a subsequent stream cutting into the deposits of an earlier one is a feature common to both sites. At Holton on a recent visit a similar feature was observed near the east end of the workings, apparently associated with a small ice-cut Channel of a later glaciation than the Norwich Brickearth. In 1953 the Holton section was much nearer the road and the whole section was composed of the inclined beds of flint shingle. It was several years before any appreciable amount of white sand was exposed. At its maximum thickness it extended nearly half way down the section, but in recent years less sand is exposed. No excess of this sand was observed in the short-Iived working across the Blyth Valley at Wenhaston where, so far as is known, no bones were discovered, however, a Cetacean vertebra and an elephant metapodial turned up on farmland in the parish. T h e area of Bulcamp, Blythburgh, and Walberswick appears to be an outcrop of Norwich Crag in the middle of the Westleton
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Beds. At Bulcamp below the turf of the Valley slope the Crag is mollusciferous and possibly mammaliferous since the calcaneum of Equus robustus has been recorded from the hamlet. The Blythburgh Heath deposits confounded the original surveyors, they confessed that they were unable to decide if the deposit was marine or glacial. It was the son of a Southwold clergyman who discovered the first clue, the vertebra of a whale. This proved that the gravelly sands were of marine origin and the subsequent unearthing of elephant remains established their relationship with the Norwich Crag. An exceptionally deep excavation at Walberswick was made in featureless sand with no indication of bedding. It is of interest that bones, etc., of the Norwich Crag mammalian fauna, both marine and terrestial, are cast ashore by storms on Walberswick beach.
Norwich Crag The Norwich Crag is largely unfossiliferous sands with beds of clay and occasional layers exceptionally füll of shells, which at Easton Bavents cliffs are exposed only when the vagaries of the North Sea permit. In certain seasons the beach level is built up high enough to conceal the bed, at other times the beach is scoured away and for a brief spell the shell bed, or beds—there are two—is, or are, revealed. More often they are hidden behind masses of fallen cliff. Readers are warned that for an unknown number of years the landowner has been losing acres of farmland and as a result objects to visitors digging in the cliffs, anyone so doing is committing an act of trespass and are liable to a penalty of £20. This is unfortunate since there is no other Suffolk site where this particular shell fauna can be seen. There is a pit on the heath close to Shellpit Cottages, Aldringham-with-Thorpe, and not far from the former Thorpe Halt at the railway crossing. The exposure is partly concealed by a wartime concrete structure. This site has a similar fauna of undersized shells like that hidden below the grass roots of the Sizewell Warren Rifle Range, near the 100-yard firing point where once there was a small pit which has been filled with refuse. The same fauna occurs under the village of Wangford and there is a very limited exposure at the south-east corner of Wangford Common Covert, next to the gravel pit. T h e Sizewell fauna is listed in Part 3 of these Contributions. In Norfolk, Bramerton is noted for its shell fauna in which Littorina littorea is exceptionally common. It was here that an incomplete horn core of a gazelle, G. daviesi, was discovered. It is unlike G. anglica in being straight and not curved. Only three mammalian fossils are recorded from Sizewell Crag, a unique third upper molar of Rhinoceros, an upper molar of Megaceros cf. verticornis and a piece of a limb bone of a small species of deer, possibly Datna nesti nesti.
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Düring the latter part of the last Century a site known as Yarn Hill was well known for its wealth of mollusca, eighty-eight species against forty-one for Easton Bavents, Clement Reid's list from "The Pliocene Deposits of Great Britain" is repeated below:— Actaeon noae y Turritella terebra .. ye A. tornatilis ye Valvata piscinalis y Buccinum dalei e Voluta lamberti .. y B. undatum ye Bulla alba y Albra abra y B. lajonkaireana y A. obovalis e B. regulbiensis y Anomia aculeata y B. truncata y Artemis lincta e Calyptraea chinensis y Astarle borealis ye Cerithium tricmctum y A. compressa ye Chemnitzia rugulosa ...... y A. sulcata y C. acicula y Cardium edule ye Helix arborustum e C. groenlandicum y H. hispida y C. nodosum y H. pulchella y Circe minima e Hydrobia subumbilicata y Corbicula flumenalis y e H.ulvae —_ y Corbula gibba ye Limnea palustris y Cyprina islandica ye L. peregra ye Donax trunculus} y Littorina littorea ye Leda oblongoides ye L. rudis y L. lanceolata y Melampus pyramidalis y e Lepton nitidum y Nassa incrassata .. y Lucina borealis ye N. granulata y Mactra arcuata ye N. propinqua e M. ovalis .. ye N. reticosa e M. solida ...... y Natica alderi y M. subtruncata ye N. catena y Modiola modiolus y N. catenoides e Mya arenaria ye N. clausa y M. truncata ye N. helicoides ye Mytilis edulis ye N. hemiclausa y Nucula cobboldiae ye Paludina media y N. tenuis ye P. vivipara e Pecten opercularis ye Planorbis complanatus y P. princeps ye P. spirorbis y Pholas crispata y Pleurotoma bicarinata ...... y Pisidium amnicum y P. turricula y Saxicava arctica y Pupa muscorum ..... y Scintilla ambigua y P. umbilicata y Scrobicularia plana y Purpura lapillus ye Solen siliqua y Ringicula ventricosa y Spraerium corneum e Rissoa semicostata y Tapes virgineus y Scalaria clathratula ...... y Teilina fabula e S. groenlandica ye T. lata ye S. trevelyana y T. obliqua ye Succinea putris y T. praetenuis ye S. oblonga y Thracea sp y Trochus tumidus y Trophon antiquus y = Yarn Hill* (Neptunea antiqua) y e e = Easton Bavents Cliff Trophon antiquus (Neptunea antiqua) var. contraria y
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The nomenclature of some of the species has been revised in recent years but interested readers will no doubt be familiar with the current terminology. " T h e Yarn Hill Pit was not marked on the map, but it is situated on a small peninsula on the north side of the marsh, half a mile west of Potter's Bridge" (South Cove). The shell beds were below the Baventian Clay. The site was notable for the number of non-marine land and freshwater shells. The valve of Corbicula flumenalis which was unique but during 1969 a second shell was discovered at Wangford near Hill Farm. The non-marine shells at Yarn Hill contributed to the use of the term "Fluvio-marine Crag" for the Norwich Crag by some authors, others preferred "Mammaliferous Crag" which raised the argument that there was no reason to suppose the Red Crag was less mammaliferous than Norwich Crag. Latter day investigations have shown that the Red Crag Sands are not particularly rieh in the remains of the coeval mammalian fauna and there is now little evidence to indicate many were found during the coprolite diggings. Those recorded are all from the Newbournian zone or Boyton, fairly limited areas. Bones of the same mammalian fauna occurs from the lower Red Crag through to the whole Crag Series to the Weybourne Crag of the Norfolk coast, including the Westleton Beds of the Blyth Valley where the indications are that fossils are probably more plentiful than the number collected owing to excavation by machines. Although the Southwold area has sections along which one may walk many times and see nothing, it is comparitively rieh in fossil bones, parts of elephant bones or teeth being the most abundant. The fauna includes:— Anancus arvernensis Archidiskodon meridiotialis Equus robustus Megaceros verticornis M. savini Euctenoceros ? ctenoides E. sedgwicki E. falconeri E. tetraceros Dama nesti nesti
D. clnctoniana? Machaerodus cf. crenatidens Felis pardoides Cards vulpes Lutra sp. Castor europaeus Trogontherium minus Arvicola intermedius Cetacea Fishes Seafowl indet.
The position regarding the Norwich Crag Mastodon is still uncertain, judging from the condition of some teeth of Anancus arvernensis, E. T. Newton thought speeimens might be coeval with the Crag. Presumably these are the speeimens from Horstead and differ somewhat in the fossil condition, there are also differences in the form of the teeth which seem not to have cut the gum and been functional, the mamillae forming the ridges are less conical with blunt rounded tops. They are reputed to have been found in 1880 when the "skeleton of a Mastodon" was found. H. B. Woodward was under the impression that only one
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tooth was discovered but this is not so. The bones appear not to have been preserved. Gazella anglica, represented by the lower part of a horn-core and A. meridionalis were associated with Anancus arvernensis in the Horstead fauna. The only other teeth of this Mastodon in a somewhat similar State of preservation camc from the Westleton Beds of Holton only recently, all the others examined have been well mineralised like those from below the Red or the Coralline Crags. Proof that some teeth were derived is provided by the record of specimens taken from loamy beds of Norwich Crag with a gravelly matrix adhering*. In Norfolk deer and elephant fossils were found, not in, but a little above the Stone Bed, below this deposit borings of marine organisms, such as Pholas, occur in the surface of the chalk. This evidence makes the Stone Bed below the Norwich Crag an equivalent of the Basement Beds of the Coralline and Red Crags but without the abundance of derived fossils from older deposits. The Chillesford Beds of loamy sand and clay of the Chillesford area are probably the only beds strictly and properly so-called. Other similar deposits with alternating layers of a similar nature were referred to this formation but they occur at various levels and must therefore be ruled out. Reid records at Aldeby "traces of deer, elephant, horse and vole," also "walrus, dolphin and guillemot". On page 109 he states: "Here lias been obtained the boreal fauna on which the Separation of the Chillesford Crag from the Norwich Crag is founded; for all the sections of the so-called Chillesford Crag itself, have produced either very few species, or an assemblage qu.ite indistinguishable from that of the Norwich Crag. At Aldeby we find a marked increase in the number of individuals belonging to Arctic forms, but at the same time there are no additional boreal species, and the horizon can only be separated from the Norwich Crag by the disappearance of a few southern mollusca, and by the preponderance northern forms." Various beds of laminated clay lithologically similar were largely accepted as Chillesford Beds and F. W. Harmer plotted these on the map and postulated the sinuous course of a river which was assumed to be the Rhine. Since some of these deposits have been proved by Dr. R. G. West not to be Chillesford Beds by Pollen Analysis and Professor B. Funnell found the microscopic marine Foramnifera were those inhabiting cold seas, the formation is now known as the Baventian Clay. No mammalian or other macro-fossils have been found in the deposit. The proximal end of the Aldeby walrus femur in the Norwich Museum is unmineralised but none of the other mammalian fossils recorded by Reid have been seen. A metapodial of elephant from the "Chillesford Beds" at Coltishall, Norfolk, in •Reid, C., Pliocene Deposits of Gt. Britain 1890, pp. 117-118.
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the Geological Survey Collection has some mineral impregnation. At Chillesford only the vertebra of a whale has been mentioned in literature. The deposit at the base of the Covehithe cliffs which was regarded as Chillesford Beds in the original survey contains occasional shells, presumably derived from Norwich Crag, but none of the species found at Chillesford or Aldeby. It is undoubtedly Norwich Brickearth. At Easton Bavents, while no bones or other fossils have been found in the Baventian Clay, elephant teeth and other vertebrate remains have been taken from the top of the Norwich Crag at its base. A similar Situation obviously occurred in the relationship of the Weybourne Crag and the overlying Forest Bed Series. In the recent examination of some hundreds of Crag and Forest Bed fossils, a number have been found to have part of the Weybourne Crag matrix on the underside and traces of Forest Bed on the upper side. These have invariably been labelled "Forest Bed" and this raises the question of how many specimens from which all trace of the matrix has been removed, either in cleaning the specimen or in the case of bones picked up from the beach having been washed clean by the sea, are reliably labelled. In some instances the fossil condition of bones, etc., is indicative of a former Crag matrix, in particular the "Black Bones" in a stony condition are regarded as more likely to have originated from Weybourne Crag than any of the Forest Bed Series although blackened bones and teeth do occur the fossil condition differs. The Crag "elk", Libralces gallicus, has its earliest record from the Easton Norwich Crag and it also occurs in the Westleton Beds, but it was first recorded as a Forest Bed species. Several antler bases have been obtained from the Norfolk coast at Runton and all are quite black and stone-like and could well have been found on the beach having been eroded from the Weybourne Crag. The larger "elk", L. latifrons, antlers are mostly in a similar fossil condition and likewise have no documented history beyond "Forest Bed" which in some instances is patently an assumption. In general bones or antlers from Weybourne Crag are brown due to iron staining and slightly glossy, whereas specimens from the "iron-pan" which is probably Crag are much more impregnated with iron Compounds and are rust coloured. "Iron-pan" fĂźll of mollusca occurs on the surface of the chalk and is exposed at low tide. Parallel to the Cromer coast there is a shallow Channel normally filled with water at low tide, the water oozes from the base of the cliffs and evidently is charged with dissolved minerals which rapidly stain objects lying in the Channel, at first deep yellow
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which deepens to a rieh brown. It may be that the brown of sub-Crag bones could have acquired their colour in a similar way.
Kessingland There is another problem with regard to speeimens labelled "Forest Bed" from Kessingland anent bones supposedly from the Suffolk extension of the Forest Bed Series. T h e deposits northward from this Parish to Pakefield, Lowestoft, are rather complicated, J. H. Blake considered the Chillesford Clay alternated with the Forest Bed Series and regarded the mammaliferous gravel underlying laminated clays as Norwich Crag. Reid identified Blake's laminated clay as fluvatile or estuarine clay of the Forest Beds, regarding the mammaliferous gravel as its basement on the grounds that the mammals were "characteristic Forest Bed species, not Norwich Crag forms". Of course at that time nothing was known of the relationship of the Early Pleistocene mammals (at that time thought to be uppermost Pliocene) most of which are represented bv fossil remains in all the Crag Series, as well as the Cromerian Forest Beds and the relationship with the Villafranchian faunas of Europe*. According to Reid the Forest Beds appear to rest on a channelled surface of Chillesford Clay or Norwich Crag along the coast between Kessingland and Pakefield and he states that "red shelly Crag was met with at about the level of low water". Blake also records the red shelly sand with the additional information that Neptunea contraria had been found, this species is abundant in the Suffolk Red Crag to the south. This data has considerable significance which was not realised at the time the observations were made. An examination of fossil bones in the Yorkshire Museum from Kessingland, also in other institutions, led to a very strong impression that they were from a Crag deposit and not from a Forest Bed Stratum as the meagre labels indicated. One fossil at Norwich which actually was of Forest Bed age had some of the clay matrix preserved and was unique in having a label with geological data also. T h e bones in question either had ferruginous sand adhering, or there was Crag-like sand in hollows or in cavities, some had the characteristic brown glossy surface usually found on bones from Crag but not without exception. An elephant humerus in the Geological Survey Collection has a type of mineralisation exclusive to Crag Sands and if the record regarding the locality from which it was taken is to be relied on, there can be no question other than its matrix was probably Norwich Crag. Other fossils do not have the same degree of mineralisation but the condition of bones from Norwich Crag differs greatly. •Reid, C., pp. 134-135.
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It was understood from conversation with older workers that the mammaliferous site at Kessingland was only exposed at low tide springs. This leads to the inference that the deposit then exposed was either Norwich Crag or part of the "red shelly sand" filled Channel mentioned by Reid, the existence of which was unknown until there was recent discussion on the problem of the true age of the supposed Cromerian fossils. The problematic bones are quite unlike the fossils which have been examined from the deposits rightly belonging to the Cromerian Forest Bed Series, namely the Rootlet Bed which occurs below the Norwich Brickearth at the foot of the cliffs to the north. Most of the Kessingland fossils are fragmentary bones of elephant but at York there are five antler bases of Megaceros verticornis, one with its pedicel, and some cervid limb bones, all with a dark brown sandy matrix quite unlike the blue Cromerian Clay at Kessingland. One thing it is most important to remember is that owing to continued coastal erosion the sites investigated by the surveyors between 1880-90 were some unknown distance from the present beaches so there is no possibility of re-examining the beds they observed. The changes in the Easton Bavents cliff sections during the past quarter Century are marked. It cannot be doubted that the present sections are unlike those seen during the geological survey by William Whitaker in 1887, and even more unlike the cliffs during the 1840s when the coastal erosion was commented on at the first British Association Meeting at Ipswich, 1847. (Southwold is almost an island and in years to come, unless the present rate of erosion is stopped, it is a safe prediction that it may be an island in fact.) T h e Kessingland fauna in the Ipswich Museum was purchased at the sale in London of Dr. Frank Corner's Collection, it includes incomplete cervid mandibles representing Megaceros and Euctenoceros, also one each of pig and bear, Ursus arctos deningeri. The deer occur in both Crag and Forest Bed Series but the other two are so far unknown as members of the Crag Sands. T h e only opinion that can be expressed is that they do not appear to have come from a clay matrix. T h e mandible of Machaerodus cf. crenatidens formerly in the Backhouse Collection was sold at a sale in London for fourteen guineas to a Dublin Museum in 1907. As some Backhouse specimens are in the Yorkshire Museum and casts of the jawbone had been labelled as having been made from a specimen "at York", there was some difRculty in tracing the fossil which is unique in British geology. It is thanks to R. A. D. Markham of the Ipswich Museum who remembered a reference to the sale that it was traced. This interesting specimen has now been examined and its source
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determined as a reddish sand with more or less rounded grains of quartz thmly coated like similar sand from Crag (FIG. 32) This fossil, discovered in 1886, is well preserved apart from Z T ! T u g C t 0 t h e ? m n e - t h e c h e e k teeth are present, P 3 , p4 M l , and the amount of wear indicates that the feline was advanced tlmC deatH; h a animal1"8 * °f P P a r e n t l y belonged to a male Lankester recorded the first evidence of Machaerodus (FIG. 32) as a Forest Bed Species in 1869 (Geological Magazine, Vol. VI p. 440) and thought it resembled the canine of M cultridens rather than M. latidens of R'd Owen from Kents Cavern of a more recent geological age. Lydekker concurred with this opinion in the Quarterly Journal of the Geological Society, Vol. P" J U 9 , l n remarks regarding the jaw published in the same volume by Mr. Backhouse, but intimaied that the evidence was insufficient to justify reference to that species, an opinion well justihed as will be shown. T h e Machaerodontidinae appear in the Eocene and are renresented by Eusmilm bidentatus, the carnassial of which most closely resembles the tooth in the Fitch Collection from Norwich Crag at Norwich but no fossils derived from the Eocene are known from Norfolk. In America E. dacotensü is recorded from the Oligocene of Dakota: Hoplophoneus Cope; Pogonodon Merriam; / / . occidentalis Leidy, is of similar age. Others are Smilodon L u n d ; (Trucifelts Leidy; Dinobastis Cope; Smilodontopsis Brown) of the Amerigracills C r c e / l c / the SfrCie! are ° P e ' S- floridanus i r ahf°rmcus Matthew, and S. neogaeus. (There is a mandible of S californicus in the Yorkshire Museum, it is notable tor the extraordinary breadth of the mandibular condyle which is mm")" 1 ' compared with the Kessingland mandible with only 35
r ^
Since the publication of the fossils mentioned by Newton others custributed among various institutions have been recentlv compared and canines, complete and incomplete from Norwich Crag and Forest Bed found to belong to only one species. M. cultridens s excluded from consideration for the simple reason that according to h a b n n i this species has no crenations on either edge of the 8 Upper canines. In the British Museum (Natural History) is a detached upper canine in perfect preservation, evidently from a young animal on 18 a r l / S r , T ° f V e r y m i n u t e s e " a t i o n s (crenations), somewhat like those on the teeth of some sharks, making them verv erficient cutting Instruments. There is also the crown of another canine, lacking the tip, which is of the "Black Bones" type, coal and stone-hke, which is regarded as more probably from the
354
Suffolk Natural History, Vol. 15, Part 4
Weybourne Crag than the Forest Bed, if only for the reason that specimens from the latter differ greatly in their fossil condition, being grey in colour with little or no mineralisation. Their earlier presence in the Early Pleistocene of East Anglia is indicated by the incomplete crown of the canine found by the Long brothers at Covehithe in Norwich Crag which is preserved at Ipswich, it agrees in every respect with the more perfect teeth from the Forest Bed. The only detectable difference in any of these teeth is the slightest possible indication of a groove parallel to the posterior edge which may perhaps be accounted for as a difference due to sex. In Europe the genus occurs in the Miocene and Pliocene. T h e M. latidens of Owen found in the Upper Pleistocene cave deposits is easily distinguished by the less numerous and nodular form of the crenations. Other European species are: M. palmidens Blainville, M. jourdani Filhol, M. aphanistus Kaup, of the Lower Pliocene, M. cultridens Cuvier, and M. crenatidens belong to the Middle and Upper Pliocene. In Asia there is M. horribilis of China and M. sivalensis Lydekker, of India. Here in Britain Machairodus is shown to have been contemporary with the Mastodon A. arvernensis by the presence of remains of both animals in the Dove Holes fauna in Derbyshire, together with an elephant tooth, a rhinoceros tooth, and an incomplete metapodial of Equus sp. There are three incomplete upper canines and two upper carnassial teeth of M. crenatidens, the latter are typical of this species. This fauna is regarded as a possible survival of the Continental interval between the recession of the Pliocene Coralline Crag Sea and the incursion of the early Pleistocene Red Crag Sea. Outside East Anglia the "Bridlington Crag" according to Clement Reid "is not Pliocene, but Pleistocene, though it does contain some extinct shells, like Tellina obliqua and Nucula cobboldiae". One may wonder what his opinion would be today when only the Coralline Crag is regarded as Pliocene. About 400 miles to the north, near Aberdeen, shells of Voluta lamberti, Turritella incrassata, Nassa reticosa, and Astarte mutabilis occur in glacial deposits, apparently derived from some deposit of "Red Crag age", according to Reid, but it must be pointed out that these species are all found also in Coralline Crag. *Recently there has been an opportunity to examine the Dove Holes faunal remains from the Buxton and Manchester Museums. T h e Machairodus teeth are mostly poorly preserved in some respects, but the crowns are clearly distinctive. Most of the material is of the Mastodon, Anancus arvernensis consisting of fragmentary bones of very young animals and teeth which are deciduous, p.l, p.3, and p . f , representing nine or ten individuals.
GEOLOGICAL HISTORY
355
APPENDIX I Scientific Tests of Crag Bones Düring a visit to Ipswich, Dr. van der Vlerk undertook to have Fluorine tests made in Holland of some bones with the following results:— Whale vertebra Elephant tusk D e e r antler Horse bone Elephant teeth
Red Red Red Red Red
Crag, Crag, Crag, Crag, Crag,
Bramford no data Bramford Felixstowe Falkenham
Pretiglian Tiglian Pretiglian Pretiglian indeterminate
The Tegelen Clay (Tiglian) in Holland is equivalent to the Cromerian Forest Bed Series, the deposit has been almost entirely destroyed by excavations for brickmaking. While this evidence confirms the greater age of the Crag Series of which there has been no doubt, its main value lies in providing a method for determining if fossil bones of scientific importance but without data are actually from Crag. Samples of a number of bones from the Red and Norwich Crags and the Westleton Beds sent to the British Museum (Natural History) for radio-metric assay gave a wide ränge of results, the meaning of which is so far not clear. They give, however, a basis for further investigation and are as follows:— B r a m f o r d Red C r a g — t h r e e specimens T r i m l e y Red C r a g — o n e specimen Felixstowe R e d C r a g — o n e specimen Waldringfield Red C r a g — t w o specimens
12, 41 18 23,
19, 28 p p m ppm ppm 24 p p m
Blythburgh N o r w i c h C r a g — 1 specimen Easton Bavents N o r w i c h C r a g — f o u r specimens W a n g f o r d N o r w i c h C r a g — t w o specimens
23 p p m 10, 28, 42, 42 p p m 20, 22 p p m
Holton Westleton Beds—eleven specimens
6,11,15,21,22, 23, 24, 28 p p m ' r o u r other specimens gave similar results, i.e., 15, 22, 23, 24 p p m Deer antler W e y b o u r n e C r a g Elephant b o n e Horse bone Megaceros antler ( p p m = parts p e r million)
27 p p m 23 p p m 56 p p m 12 p p m
These results are from fossils of the indigenous mammalian fauna of the Early Pleistocene Crag Series and should prove of value for comparison if the Foxhall hominid mandible is rediscovered. Analysis of one Red Crag bone and ten from Westleton Beds by Dr. Ian Cornwall follows:—
Suffolk Natural
356
History,
Vol. 15, Part 4 LO
'S. §
«a 0
i c"2 §--s
Nil
u
2-70h
2-95
1 -30p
2-50
4-55
210
2 05
1-45
2-25
6-25
i"« 0 s K taSS ! o Q e*
1-60
cW m) - uu s S-S,™ o ms ff W) >>•5 s u . s (U >7 ^ O fe « U " „T3 "J-J3 M.a <L> o ~B 0 «ä CM- O o>
0 08 180
004 230
004 210
0-48 205
140x
002
0-02 215
004 205
002 230
008 250
006 170
006 220
P2O5
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i
Cetacean scapula
Deer bone
Cetacean bone
Elephant bone
Cetacean vertebra
Deer antler
Elephant bone
Horse bone
Cetacean bone Westleton Beds
Deer antler
Deer bone Red Crag
Description
X
Formation
Phosphates
Organic matter Alkali soluble
,
' P
CO O
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