A Contribution to the Geological History of Suffolk, Part 4

A CONTRIBUTION TO THE GEOLOGICAL HISTORY OF SUFFOLK Part 4 HAROLD E . P . SPENCER, F.G.S.

THE INTERGLACIAL EPOCHS

Introductory THE Pleistocene epoch has generally come to be regarded as covering the whole of t h e so-called " I c e A g e " b u t since it has been shown that there have been four major glaciations which covered n o r t h e r n and eastern Britain and there is evidence elsewhere of at least six earlier such cold phases during the past t w o - t h r e e million years, it seems possible that our present era may be the earlier part of an interglacial which has not yet reached its peak since the polar ice caps and m o u n t a i n glaciers are still retreating.

T h i s is the most recent of the Geological Epochs, t h e earlier periods are respectively the Age of Invertebrates, t h e Age of Fishes, the Age of Reptiles and t h e Age of M a m m a l s . It would not be inappropriate to regard the Pleistocene as the Age of Elephants since t h e remains of these animals occur in all the t e m p e r a t e intervals f r o m the Red Crag u p w a r d ; they were most a b u n d a n t d u r i n g t h e Cromerian period.

T h e true Elephants presumably developed during t h e pre-Red C r a g Sea Continental stage of the early Pleistocene of which all b u t the scantiest evidence has vanished. W i t h the early elephants were the progenitors of the Megaceridae (giant deer) and other extinct Cervidae such as t h e Euctenoceridae (comb-antlered deer), also a variety of other animals whose remains occur in t h e Crag sands and Forest Bed Series of the Norfolk coast.

Interglacials are intervals following one phase of arctic cold and preceding another, geologically represented by deposits of lake clays, detrital m u d s , fluviatile brickearths and loams, also sands and gravels of f o r m e r river systems. T h e s e deposits often contain fossil remains of the fauna and flora of these bygone ages. Formerly it was only by the study of these fossils and t h e artifacts of flint m a d e by prehistoric h u n t e r s that these beds could be identified. Occasionally leaves and seeds of plants now living in more northerly regions were f o u n d , indicating fluctuations of climate.

In t h e earliest interglacial deposits we find a large n u m b e r of m a m m a l s which became extinct presumably because of the glacial conditions which followed an interglacial b u t a few reappeared in t h e ensuing t e m p e r a t e period. O u r knowledge of t h e present representatives of some of these species and the climatic regions of the world in which they live leads to t h e conclusion that their

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prehistoric ancestors probably lived in similar habitats. F o r instance the fossil remains of the M u s k Ox imply the very inhospitable climatic conditions of Greenland and N . E . Canada at the present day.

T h e evidence of f o r m e r sub-arctic conditions provided by macroscopic plant remains is n o w supplemented by pollen preserved in clays, etc. T h e new technique of Pollen Analysis has been applied to enlarge our knowledge not only of s u b arctic flora but also of the flora of the warmer intervals.

The pollen of trees and other plants is distributed by winds and the quantity which fails to accomplish its normal p u r p o s e of fertilisation is incalculable, these pollen grains fall into water and are buried in the m u d and are thus preserved for h u n d r e d s of t h o u sands of years. Pollen Analysis was initiated in this country by Dr., now Professor, H . G o d w i n at the Cambridge University S u b D e p a r t m e n t of Q u a t e r n a r y Research and has been continued in our area mainly by D r . R. G . West, but also by Drs. S. L. Duigan and C. T u r n e r .

In Pollen Analysis the Separation of the pollen grains f r o m the matrix is a tedious process involving the t r e a t m e n t of t h i m b l e f u l l sized samples taken at about ten centimetre intervals f r o m ten, twenty to perhaps a h u n d r e d feet t h r o u g h o u t a deposit. Having separated t h e pollen grains they have to be m o u n t e d on glass slides and identified by means of a powerful microscope and counted.

T h e relative n u m b e r s of different species of trees and other plants in successive horizons can t h u s be ascertained and changes in climatic conditions shown, e.g. f r o m Birch to Pine and then to mixed Oak Forest.

Fossil land and freshwater shells have also great value as a means of estimating the probable climatic conditions prevailing during the laying down of a deposit. T h e writer's discovery of the Bobbitshole Lake Beds in Belstead Brook Valley at Wherstead about 1950 with its exceptionally rieh shell fauna enabled B. W . Sparks, of Cambridge, to relate molluscan species to the pollen sequence for the first time.* It is h o p e d that work on the beetle elytra (wing C o v e r s ) f r o m the detrital m u d can be completed by D r . G . R. Coope of Birmingham University. Some exotic species have been f o u n d but not all are so far identified.

Interglacial deposits are generally only r e m n a n t s of the beds laid down d u r i n g t h e t e m p e r a t e periods between glacials. T h e y include t h e surviving portions of river terraces of which t h e higher are the earlier, the Valleys having been cut deeper by each successive stage of erosion. T h e most recent interglacial deposits •Phil. T r a n s , of the Royal Soc., 1957, vol. 241, pp. 33-44.

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often occur below the present flood piain formations in existing Valleys. Other interglacial beds occur in eastern Britain at plateau level as the surviving remnants of former lakes or river systems. One of the most notable of these is the Hoxne lake clays which are situated between two subsequently formed Valleys tributary to the Waveney which forms the Suffolk-Norfolk border.

A chain of elongated patches of brickearth to the east of Ipswich undoubtedly represent another former river Valley of Hoxnian age judging from the wealth of Acheulean flint artifacts from both sites.

Varved, laminated clays or brickearths usually represent the retreat stage of a glaciation and the beginning of an improvement in climatic conditions but in some instances, such as the deposits of the Marks Tey area in Essex, they indicate preglacial- deterioration of climate.

It is the fossil remains of the molluscan and mammalian faunas which were formerly the means by which a determination could be made of climatic and topographic conditions before the more detailed data from Pollen Analysis were applied for more scientific investigation of interglacials. This technique can however only be used with very fine grained deposits such as clays and silts and the older techniques must be used elsewhere. Mollusca are adapted to certain conditions such as bog, marsh, reed beds and various woodlands, etc. Similarly mammals are indicative of the types of country in which they lived, e.g. red deer, woodland and horses, open grassland, but pollens prove the existence not only of grass and trees, but which grasses or other herbage as well as what type of trees, in particular types of Vegetation no longer normally part of our flora. Some fossils such as the bivalve mollusc Corbicula flumenalis and the pond tortoise Emys orbicularis indicate a warmer climate.

Few interglacial sequences are complete because there is a good deal of evidence to show that toward the latter phases of a temperate period there was considerable erosion probably due to very severe deterioration of climatic conditions. The oncoming of the subsequent ice sheet destroyed part of what was left. This is particularly true of Hoxne and probably of Bobbitshole also. As to the earlier glacials and interglacials all but scanty traces appear to have been obliterated by marine incursions. In PART 1 of this series reference was made to the presence of igneous, Jurassic, Cretaceous and other erratics, also striated stones similar to those found in glacial tills, or boulder clays, which occur in the Basement Bed of the Red Crag implying at least one earlier glaciation because these rocks, etc., were undoubtedly transported by ice from the north. Similarly, the rare occurrence of Sub-Red Crag bones in Lowestoft and Gipping Tills may well be recorded here as evidence of the destruction of formerly existing Crag beds to the north of the present limit of that formation. This destruction is

151 also shown by the quantity of shell fragments derived from the Red Crag in Gipping outwash gravels at Creeting St. Mary, Sproughton and Woodbridge. The derivation and transport of readily identifiable material goes far to prove the destruction of earlier formations by ice, a fact which seems seldom to have been recognised. At Holton, in the Blyth Valley, a limb bone of a Jurassic Plesiosaur in the upper levels of the Norwich Crag Series (Westleton Beds) implies the presence offloatingice which must also have transported the occasional sub-angular blocks of various rocks found there. The relatively high level of the base of the Red Crag in north-east Essex and south-east Suffolk taken with the abundance of shells indicative of warmer conditions, suggests transport by land ice for the Sub-Red Crag erratics and not sea ice as was supposed by P. G. H. Boswell.

GEOLOGICAL HISTORY

Red Crag? Interglacial

(Earliest Pleistocene) The Red Crag Marine Sands are generally regarded as the earliest deposits of the Crag series which extend from north-east Essex to northern Norfolk. There are three main divisions, Red, Norwich, and Weybourne Crags. The former is also arbitrarily sub-divided on the basis of the percentages of extinct and living species of mollusca from south to north into three zones, Waltonian of north Essex, Newbournian of south-east Suffolk, and Butleyan.

The molluscan faunas vary within the zones, e.g. one locality may have an abundance of Mya arenaria, whereas a short distance away this species may be absent. The presence of the more robust shells derived from the older Pliocene Coralline Crag, such as Cardita senilis, which cannot be distinguished from the indigenous shells tends to throw some doubt on the validity of percentages.

Although to an experienced Student of Red Crag problems there can be no doubt regarding the fact of a pre-Red Crag glaciation, the true relationship of this marine episode to that of the Norwich Crag is as yet unknown. The base of the Red Crag is not seen anywhere below the present sea level but the molluscan fauna of Walton-on-Naze (Waltonian), generally supposed to be the oldest part of the Crag Series, represents a warm phase of the period and yet the Crag sands in north-east Essex lie on London Clay at from fifty to one hundred feet above the ordnance datum. As it is believed that the sea level is lowered in proportion to the severity of a glaciation the earliest deposits of the Red Crag marine episode would be expected to occur at a much lower level. The recorded base of the Norwich Crag at Southwold is at minus 170 feet and its highest occurrence in Norfolk about 150 feet O.D., which corresponds to the Red Crag Beach at Battisford in East Suffolk, also 150 feet.

The molluscan fauna of the Red Crag differs from that of the Norwich Crag chiefly in the presence of incredible numbers of

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shells of Neptunea contraria (the "left handed whelk"). This species at the present time lives mainly on the Spanish coast and in warmer seas than the present North Sea, implying that the middle of the period of the Red Crag sea was warmer than that of the Norwich Crag in which the northern species of Neptunea, N. antiqua is represented. Volumes have been written about the Crag mollusca of which a monograph, " T h e Crag Mollusca" Vol. 1, by Searles V. Wood, published by the Palaeontological Society in 1848, with volume 2 and supplements later, was the first major attempt to describe all the species. More recently F. W. Harmer, with the co-operation of Alfred Bell, dealt exhaustively with the gasteropods in the "Pliocene Mollusca of Great Britain" issued in a series of parts by the same Society between 1914 and 1925. Harmer had intended to deal similarly with the lamellibranchs but he did not live to see the final part of his monograph through the press, this was done by Bell although he was over ninety. Space does not permit much discussion of the mollusca of which much has been written by others more conversant with this very specialised field.

There is one point, however, which seems to have escaped attention, i.e. the exceptional size of the shells from the Newbourne and Waldringfield pits. Zeuner in "Dating the Past" (1946), p. 376, gives a table in which the Newbournian Zone is referred to the "Early Glaciation I". Nothing is less indicative of cold conditions than giant shells of Neptunea contraria which species today prefers warmer seas than that of our present east coast. There is also the factor of a higher sea level than would be expected in a period of severe cold.

All the Crag Series were originally regarded as belonging to the Pliocene in spite of the discovery of fossils in and below the Red Crag proving the presence of elephants and horses during period of the Red Crag Sea. These were either ignored or explained away.

Professor J. S. Henslow, a former President of the Ipswich Museum, first drew attention to the less mineralised bones found in the Crag Sand and not in the Basement Bed. He regarded these as the remains of the indigenous mammalian fauna of the period.

At no time does any description of any of these fossils appear to have been given, but two classes of bones, heavily mineralised and less mineralised, were referred to in one of the Geological Survey Memoirs about 1885.

It was following a visit to Ipswich Museum in 1953 by Dr., now Professor, Azzaroli, of Florence, when studying Crag and Forest Bed Deer, and when he recognised an incomplete antler of Euctenoceros falconeri* from Bramford, that the writer was led to make a serious study of the contemporary Crag mammals. •Bulletin of the British M u s e u m (Natural History) Geology, 1953, vol. 2, no. 1, p. 43.

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The results of this study ('Prehistoric Deer of the East Anglian Crags', Trans. Suffolk Nat. Soc. 12, 262-266, 1963, and ' T h e Contemporary Mammals of the Crags', loc. cit. 333-334) show that the Crag series is linked with the Villafranchian of Southern Europe and that the Red and Norwich Crags have a common mammalian fauna, many species of which are found also in the Cromer Forest Beds'. T h e fauna includes:— Elephant

Archidiskodon

Horse

Equus robustus

Deer

Megaceros verticornis M. savini Euctenoceros falconeri E. sedgwicki E. tetraceros Dama nesti nesti Gazella anglica (sub Crag) Felis pardoides Ursus cf arvernensis Canis lupus Vulpes vulpes Castor sp.

Lepus sp.

Hystrix sp.

Antelope Leopard Bear Wolf Fox Beaver Hare Porcupine

meridionalis

Falkenham, Trimley, N e w b o u r n e and Foxhall Felixstowe and Waldringfield Felixstowe and Trimley Felixstowe Bramford and Bawdsey?

Bramford Felixstowe Bramford Felixstowe and Martlesham Newbourne Bramford and Woodbridge Boyton (post Crag)* Boyton Ipswich, Beggar's Hollow Boyton Bramford and PFelixstowe

Except for the latter six genera this fauna is much better known from the Norwich Crag sands because of modern exploitation for gravel, particularly in the Westleton marine pebble beds where terrestrial and marine faunas occur together. Two problematic rhinoceros teeth and a limb bone seem to be the only evidence of the genus from Crag.

Possibly the smaller species would be better known were they not so likely to be overlooked. Likewise, members of the more minute molluscan fauna are not well represented in collections.

The Norwich Crag differs from the Red Crag in its more variable character. A great part is unfossiliferous sands, apart from sparsely distributed bones or teeth, with interbedded gravelly and argillaceous layers and occasional beds rieh in molluscan remains. T h e Westleton marine shingle beds of the Blyth Valley region, which although largely devoid of shells do contain evidence of their former mollusciferous character, are indubitably part of the Norwich Crag by reason of the relatively large number of bones of Crag elephants, deer and horses, etc. therein.

Owing to the presence of clay zones in the Norwich Crag it has been possible to apply the new technique of pollen analysis to this part of the Crag Series with the result that the Norwich Crag has proved to be an interglacial with a cool oscillation toward the end of this phase. *Now proved not to be fossils of Crag age.

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T h e establishment of the N o r w i c h Crag as an interglacial has not helped to solve t h e relationship of this m e m b e r of t h e senes to t h e p r e s u m a b l y older Red Crag in which t h e former argillaceous lavers have been indurated with hydroxide of iron, to which mineral t h e red colour of the sand is due. Parts of t h e Red Crag sands below t h e reach of percolating water, are, however, grey, rarely green, sometimes blackish and often whitish. T h e u p p e r part to a varying d e p t h is usually decalcified and most frequently brown.

F e r r u g i n o u s concretions in the decalcified zone very often have impressions of shells proving its former mollusciferous nature.

T h e r e is n o known site where the Basement Bed of t h e Red Crag is recorded below present sea level but the lowest recorded level lor any Crag sand is 170 feet below sea level at Southwold. W i t h no samples f r o m this level available it is not possible to d e t e r m i n e it this Crag is truly N o r w i c h Crag, as is generally beheved, or an older portion of t h e Red Crag. At Aldeburgh Brickfield t h e Pleistocene C r a g rests on Pliocene Coralline Crag at a b o u t forty feet O . D . and at Southwold, twelve miles to the north, it is about 200 feet lower Preliminary bores for the Sizewell power Station p e n e t r a t e d to 1ZV feet without reaching the underlying formation and the lowest eighteen feet was grey, a description more like the lower part ot t h e R e d Crag t h a n the N o r w i c h Crag*. T h i s site is about four miles f r o m A l d e b u r g h which implies a descent in excess of thirty feet per mile. + D r B M F u n n e l l f o u n d Pliocene F o r a m n i f e r a in sand samples f r o m ' t h e Sizewell borings which is not surprising as t h e Pliocene Coralline Crag of A l d e b u r g h and T h o r p e n e s s m u s t have been eroded by t h e Pleistocene Crag seas. I t is possible that t h e Pliocene M a s t o d o n teeth eroded f r o m t h e N o r w i c h C r a g sands at Easton Bavents cliffs may have been similarly d e n v e d f r o m t h e Coralline Crag Basement Bed although these heavily mineralised fossils exhibit little or no sign of beach rolling. T h i s however, m a y be due to the m o r e sandy nature of the beds in w h i c h t h e y n o w occur c o m p a r e d with the usually stony nature of the Red Crag Basement Bed. A n e n t this it is important to consider the absence of records of other Pliocene mammalia such as Axis pardinensts f r o m N o r w i c h Crag, of which shed antler bases and teeth are fairly c o m m o n below t h e Red Crag. ( T h e s u b - C r a g m a m m a l i a will be dealt with in t h e final part of this series on Suffolk geology.)

T h e r e are n o k n o w n glacial deposits below t h e Red C r a g b u t t h e r e is some evidence t h a t it was laid down d u r i n g an interglacial.

1 he q u a n t i t y a n d character of striated erratic rocks and fossils in the Basement Bed is evidence of t r a n s p o r t b y ice and it was t h o u g h t t h a t floating ice was the agency. It has already been stated t h a t •Personal communication f r o m S. C. A. Holmes. f N o w Professor at t h e University of East Anglia.

155 during a glaciation the level of the seas are lowered and the melting of great masses of ice raises the sea level. The earliest Red Crag was believed to be that of north-east Essex, where the base rises from about 35 feet O.D. at Walton-on-Naze to 100 feet at Wix, with a pebbly beach deposit at Battisford, Suffolk, at 150 feet.

This is concrete evidence of a rising sea level during the deposition of the Red Crag sands such as would be expected for interglacial conditions.

At Walton the Crag has an abundance of shells of the mollusc Neptunea contraria, a species now living in Spanish waters, notably in Vigo Bay, indicative of somewhat warmer climatic conditions in the North Sea region during the Red Crag period. This implies that the Red Crag interglacial was well advanced at the Walton stage of the formation of the deposit. In the Newbournian Zone between the Orwell and Deben estuaries some shells of Neptunea are of exceptional size and all are more robust. Many shells of other species exhibit increased size which suggests very favourable climatic conditions. Extensive sieving in the Crag at Beggars Hollow, Ipswich, has shown a heavy mortality amongst the juvenile Neptunea contraria, this is implied by the vast number of shells from a length of a quarter-of-an-inch upward. The more northerly Butleyan Zone has fewer Neptunea and they are notably smaller and accompanied by species indicative of climatic deterioration. A bore at Benhall Street, near Gt. Glemham Park and two miles south-west of Saxmundham has proved an extension of the Butleyan Red Crag north of the Aide Estuary. The Benhall sections follow:— GEOLOGICAL HISTORY

Bore A 29'O.D. Bore B 26' O.D. Soil 1ÂŁ' Peat 10' Sandy clay j' Gravel 71' Grt >vel 174' Sand and shells (Crag) 42' Sand 10'\ Flints 2' Sand and shells (Crag) 36'/ Soft Chalk 10' Klints 2' Hard Chalk 128-200' Chalk 132-200' The base of the Crag is minus 36' in A, and 33' in B

This site is about a mile to the south and seven-and-a-cjuarter miles south of west from Sizewell. It has generally been considered that all Crag north of Aldeburgh is Norwich Crag* but the material from the Benhall bores and its fauna is obviously Red Crag, although grey in colour owing to the fact it has not been subjected to oxydising influences. It is conceivable that this grey zone dips eastward along the slope of the Chalk surface and may be part of the Grey Crag recorded from the Sizewell bores.

Since the foregoing was written the Chillesford Church pit has been reopened showmg a clear section from the Gipping Till well down through the Chillesford Beds into the Butleyan Red Crag. The intermediate strata appear to be similar to the Scrobicularia Crag at Aldeburgh Brick>ard but a detailed examination has yet to be made.

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The Molluscan fauna of the Red Crag has been dealt with by Wood, Harmer and numerous authors therefore it is not proposed to add to the literature, all that need be said is that it differs greatly from that of the Norwich Crag.

Norwich Crag Interglacial The true relationship of the Norwich division of the Crag Series to the Red Crag has not yet been established, the lithology and molluscan fauna differs greatly. The Norwich Crag is mainly sandy with beds of clay and gravel and occasional strata largely composed of shells but there are areas such as the northern part of Sizewell Warren, Aldringham Heath, and Wangford which are rieh in shells, also Broome Heath, Bungay, and Bramerton in Norfolk.

It has been supposed that the Crag series is older in the south and the arbitrary zones, based on the percentages of living and extinet species, are progressively younger toward the north, i.e. the succession is lateral and not vertical. There is, however, a great disparity in the base level of the Red Crag and Norwich Crag. At Aldeburgh the Scrobicularia Crag rests on Pliocene Coralline Crag thirty-forty feet above the sea, but at Southwold twelve miles to the north the Crag base is minus 170 feet. Borings at an intermediate site for the Sizewell Atomic Station, penetrated to 129 feet without reaching the Crag base. Counting from Aldeburgh a fall in the base level is in excess of 30 feet per mile. The Coralline Crag, however, extends northward to Thorpeness two miles from Aldeburgh and dips below the sea (blocks are cast ashore by storms). Basing calculations on these data the descent of the Crag base must exceed over 60 feet per mile thus a great deal of work has to be done to establish if all the Crag beds north of Aldeburgh are indeed Norwich Crag or if the lower levels are older than the known Red Crag as they could well be if the grey lower zone is equated with the Benhall Red Crag to the west, where its base level is between thirty and forty feet below O.D. While the molluscan fauna differs from the Red Crag, all the Red Crag mammalia are represented in the Norwich Crag sands and numerous bones and teeth have been collected during the past fifteen years mainly from the commercial gravel workings but also as a result of coast erosion. By far the greater amount of fossil bones, etc. have been obtained from the hitherto problematic Westleton Beds, sensu stricto, in the Blyth Valley. Cetacean vertebrae frequently occur with remains of land mammals.

Westleton Beds The Westleton Beds are an integral part of the Norwich Crag series and occupy a roughly triangular area from Minsmere, Westleton, Wenhaston, Haiesworth, to Henham Park and Reydon and consist of a series of superimposed pebble beaches and thick

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masses of white sand. Similar white marine sand in southern Suffolk has been seen to pass down into normal shelly Red Crag.

A much decayed scapula of a whale came from the white sand at Holton. Impressions of shells occur in indurated masses of sand, and shells occur poorly preserved in a submerged Stratum in which the pebbles and shells have been cemented with iron sulphide at an unknown depth below the watertable. Bones of various extinct deer, horses and elephant, encrusted with pyriteous matter occur at the same level. At higher levels the presumed original pyrites has been converted to limonite where water has readily percolated through the very pervious strata and at the highest levels bones have been reduced to a friable condition by the same agency. One of the very remarkable features at Holton is the extremely variable fossil condition of bones, some being heavily mineralised, others so friable that they may be crumbled in the fingers. The condition of bones from Reydon is less varied and none in a pyritised condition have so far been seen. So far as is known no bones have been recovered from the higher levels there, most are from below the watertable whence bones, evidently from a drowned elephant, appear to have been found in association. It is unfortunate that all but two small pieces of rib were taken by some unknown person so it is impossible to describe the remains beyond recording the fact that these rib bones exhibit no sign of the usual wear and tear of derived bones. Two major portions of the humerus of a cow elephant were subsequently recovered a short time later which may possibly belong to the same skeleton. Associated bones of an animal in Crag sands are of the greatest rarity.

It is notable that incomplete fossil shells have recently been found at Reydon during casual visits, they are from a level above the water and it is hoped that it may be possible to work out a fauna.

It is to be expected the species will prove to be Norwich Crag forms such as have been recorded in the past from the Westleton Beds.

Elephant remains predominate in the Blyth Valley deposits largely because the limb bones several feet in length can be broken into many fragments, there are, however, two examples of the humerus of which the distal half and two-thirds respectively have been preserved. An almost perfect elephant femur has since been unearthed at Wangford by H. D. Collings of Southwold. The former, from Holton, belonged to a young animal and the latter, from Reydon, may belong to the skeleton of an elephant already mentioned: it was broken up by the excavator but the fragments of the proximal end were not collected. Cetacean vertebrae are fairly numerous and invariably incomplete and indeterminate, portions of a much decayed scapula came from a high level at Holton. Walrus is represented by part of a tusk from Holton and a vertebra from Easton Bavents. There is an undetermined vertebra from Wangford which may be walrus.

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The terrestrial vertebrate fauna of the Norwich Crag and Westleton Beds follows:— Elephant

Archidiskodon

Horse

Equus caballus fossilis\ E. robustus J Rhinoceros sp.

Megaceros verticornis M. cf savini Euctenoceros sedgzuicki

Rhinoceros Giant Deer Deer

meridionalis

E. falconeri E. tetraceros

Elk Beaver Otter Gazelle Leopard Voles, etc.

E. cf ctenoides Dama nesti nesti Libralces gallicus Castor sp Trogontherium minus Lutra reevei Lutra sp.

Gazella anglica Felis pardoides

Easton Bavents, Holton, Reydon, Walberswick, and Wenhaston Easton, Holton and Walberswick D u n w i c h and Sizewell Easton and Sizewell Easton Easton, Holton and Dunwich Easton, Holton and Walberswick Easton, Wangford and Holton Easton Holton Holton Easton Bavents Easton Bramerton Easton Broome Heath, Horstead, T h o r p e , etc.

Easton Easton

The remains of Equus robustus from Easton Bavents consisting of fragments of a mandible with the cheek teeth, lacking the second pre-molar, also part of the left pre-maxillary with two incisors, are preserved in the Ipswich Museum and are thought to be the best fossil of the species in Europe by Prof. A. Azzaroli, who has made a special study of early Pleistocene horses. It is presumed that these remains were found following a fall of Easton cliff. All the broken surfaces are fresh and had the collector been aware of the scientific importance of this specimen perhaps he might have taken some trouble to try to obtain more of the fossil. It is evident there must have been a large part, if not a complete skull, and at present no complete skull of this species is known. Odd limb bones or parts thereof, also separate teeth are all that is usually found.

The amount of mammalian fossil material seen in recent years suggests that the term Mammaliferous Crag was by no means undeserved, but it was rejected on the grounds that there was no proof that the Norwich Crag had more fossil bones than the Red Crag. Apart from the Red Crag Basement Bed, Observation over the past fifty years has shown this to be untrue but it is due to post war large scale excavations that the true wealth of mammalian remains has been revealed.

Perhaps the greatest part of the Norwich Crag is unfossiliferous but there are richly mollusciferous areas and beds. No complete fauna will be given but the faunas from sundry sites are given,

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Sizewell Warren—Wangford (S), and Aldringham-with-Thorpe (A) are compared with a fauna list from Bramerton (B), Norfolk.

Univalves Neptunea antiqua Scala (Boreoascala) similis Turritella communis Lucoma fusiformis Melampus pyramidalis Paludestrina minuta Trochus (Gibbula) einerarius Eumargarita crassistriata Ringicula buccinea Littorina littorea Bela scalaris Natica (Lunatia) nana N. (Lunatia) catena Potamides (Phytopotamides) Calyptrea chinensis Margarita elegantisima Nucella (Purpura) lapillus Pleurotoma inermis v. nuda Succinea oblonga Paludina lenta Bivalves Cardium

edule

Mya arenaria Spisula (Mactra)

S A B

tricinctum

X X X X X X X X X X X X X X

Sizewell

X X X X X

S. (Mactra)? solida Leda myalis Mytilis edulis Lucina borealis Solen siliqua Teilina (Macoma) obliqua T. (Macoma) praetenuis Corbula striata Cyprina islandica

small size

-

-

X X X -

-

-

-

-

-

very a b u n d a n t

X X very c o m m o n -

-

-

-

X X very a b u n d a n t b u t X small size small X - X - X X X not c o m m o n X f r e s h w a t e r species X - f r e s h w a t e r species X - -

s

of

A B

X X X subtruncata

notes

X X X X X X X X X x! X J X ?

X X ?

X -

very small and fragile at Sizewell very small and fragile at Sizewell

X -

X X X X X X X

very small and rare

Since Dr. R. G. West has established the Norwich Crag as an interglacial by the pollen analysis of samples from a boring at Ludham, Norfolk, with a cool oscillation toward the end of the period which is represented in Suffolk by the Baventian clay of Easton Bavents cliffs (formerly regarded as Chillesford Beds), it seems reasonable to suppose that this fauna with its reduced size of shells and fragile cockles is associated with this deterioration of climate. The Baventian Clay contains no shells and forms a considerable part of Easton Cliffs, a southerly coastal exposure is at Aldeburgh Brickworks and it is still used at South Cove; it was formerly used at Frostenden and a former outlier existed in the Gipping Valley at Broom Hill, Creeting St. Mary, but was latterly destroyed by gravel working.

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No fauna list from Wangford is given because only a few shells were collected from the spoil heaps of trenches which had been back filled, the site is interesting, however, because the most complete antler of Euctenoceros tetraceros was unearthed but unfortunately all the fragments were not collected. The shells, however, are similar in size and include the same species as the Sizewell Warren site, G.R. 475640. A largely overgrown pit by Shell Pit Cottages on the heathland, Aldringham-with-Thorpe, appears to have much the same fauna with undersized shells, G.R. 642608.

While the Sizewell Warren site is unusually fossiliferous it is curious that the extensive excavations for the Atomic Power Station about a quarter of a mile to the south were made in a rather uniform sand with only fragmentary remains of shells. It is unfortunate that circumstances did not permit constant Observation during the progress of the work if only for possible mammalian remains, Megaceros, Equine and Rhinoceros remains having been recorded from the area.

Neptunea contraria, so common in the Red Crag, is replaced by N. antiqua in the Norwich Crag but it is less numerous: this is a northern species which occurs on Suffolk beaches at the present time, particularly on Bawdsey beach which in recent years has become a mass of shingle where recent shells are often mixed with Crag species. Incidentally the shingle storm crest at Bawdsey now prevents the erosion of the cliff foot which thirty years ago kept the Red Crag sections fresh. Unless some new change occurs it is only a matter of time before the whole of the Crag section is obscured by talus. Much Crag debris has been carried across to the Felixstowe side of the Deben mouth by the action of the sea.

Weybourne Crag T h e most northerly member of the Crag series is the Weybourne Crag of the north Norfolk coast in which the bivalve Macoma balthica is a prominent species. Bones and teeth of Crag mammals occur in this Crag but detailed records are few. Recent work on the Geological Survey and Yorkshire Museums collections has shown that a number of fossils recorded as Cromerian are really of Weybourne Crag age.

Below the Weybourne Crag, lying on Chalk and exposed at low tide are patches of Crag cemented with iron Compounds which have numbers of shells with a left hand spiral like Neptunea contraria of the Red Crag. As these are very firmly fixed in the hard matrix it is not possible to extract them for detailed examination, the presence of this type in Norfolk raises the question of a possible extension of Red Crag in that region. Other Crag-like deposits exist at Bridlington and near Aberdeen, also on Iceland.

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Wangford At the time of writing the discovery of a valve of Macoma balthica on a spoil heap of a reopened pit near Wangford was mentioned by P. E. P. Norton (formerly of the Sub-Department of Quaternary Research at Cambridge, but at present at Glasgow University) in a personal communication during a recent visit.

It has frequently been said 'one swallow does not make a summer' and there is the possibility that the shell arrived there by accident, this however is considered to be a very remote chance because the site is known to but a very few geologists. The presence of M. balthica, if a genuine member of the local fauna, is stratigraphically important because it is generally considered that the species first appeared in the Weybourne Crag of the Norfolk coast, the uppermost member of the Crag series. One valve of the lamellibranch Corbiculaflumenalishas recently been found at Wangford in very shelly Norwich Crag below the Westleton Beds at Wangford. This is inconsistent with the supposed presence of Macoma Balthica.

The Wangford pit is situated along an accommodation road to a farm and the present section is mollusciferous, but it is important for another reason, for here the Baventian laminated clay occurs inter-digitated with the upper part of the pebbly deposits of the Westleton Beds of the Pleistocene Crag series. This is indicative of a close relationship between the Westleton marine beach deposits and the Baventian Clay. It is now established that the Westleton Beds are intermediate in age between the Norwich Crag and Baventian Clay, which Dr. West has found by the pollen assemblage therein to have been deposited in a cold sea toward the close of the Norwich Crag era. It is presumed some heaps of rather richly shelly sand were either in a localised pocket, or perhaps an upper Stratum which was removed preliminary to the removal of gravel, or possibly spoil from excavations in the vilage.

Only one small fragment of an elephant limb bone has been collected from this pit but some years ago a schoolboy took some cervid bones to Ipswich Museum which appeared to belong to the Crag mammalian fauna and from his vague description of their source probably came from this site. It would be interesting to re-examine the specimens in the light of greater experience of the fauna of the Blyth Valley. So far excavation has not proceeded to the depths reached at Holton and Reydon but as the site is of unique importance it should be kept under Observation.

To judge from the fragmentary remains of shells the molluscan fauna appears to be similar to that exposed by trenches in Wangford Street and at Sizewell Warren. The grid reference is 465779.

One explanation of the inter-digitation involvesfluctuationsof sea level during the Baventian phase of the Crag period, since this type of phenomenon could be produced by a rising sea level with erosion by the Baventian Sea encroaching upon the coast of a post

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Westleton terrestial interval. A layer of mud accumulated which eventually became buried under a shingle beach on which another layer of mud was deposited, which in turn was buried and the cycle repeated. Much the same phenomenon is illustrated in FIG. l l o f Part 2 of these contributions, where London Clay is interdigitated with brickearth as a cliff was eroded during a rising water level during an aggradation stage of the Gipping-Orwell system, probably the Ipswichian interglacial.

The Cromerian Interglacial In the study of interglacials one is faced with the problem of which came first, like that of the chicken and the egg. The earliest surviving East Anglian glacial deposit is the Cromer Till which overlies the CROMER FOREST BED SERIES, our earliest series of interglacial deposits generally recognised, but so far no tili has been detected below it. Pollen analyses of the Forest Beds are not strictly comparable with the Taxandrian of Holland, the nearest Continental deposits of presumably similar age. This could possibly be due to the probable deltaic eharacter of the deposits forming the series. It is believed that comparison of the mammalian faunas might resolve this problem. There appears to have been a cold oscillation during which arctic flora flourished leaving seeds, etc. in the so-called Arctic Bed of the Series. It is not known if the remains of musk ox, walrus and other mammals usually associated with a northern climate were derived from this deposit as the bones were most often found on the shore after storms, or have been trawled from the sea floor.

The Cromerian Series of the Norfolk cliffs are a complex of various arenaceous, FIG. 23, argillaceous and gravelly beds in some of which drifted roots of trees have been found. They have been exposed by coastal erosion at the foot of the cliffs at intervals along the north Norfolk coast round to Kessingland in Suffolk. Most notable is the extraordinary assemblage of mammalian remains, many of which had ancestors living throughout the preceding Crag period, amongst them animals such as the Hippopotamus which imply warm climatic conditions.

While the main part of the Cromerian lies outside our area one bed, the Rootlet Bed (so-called because of the remains of roots therein) extends southward to north-east Suffolk where it is, or has been, exposed at the base of the cliffs between Gorleston and Lowestoft and as far south as Kessingland, where the mammaliferous horizon is said to be exposed only by the lowest tides. The Bed is sealed in by the Norwich Brickearth, which is regarded as the equivalent of the Cromer Till, and during the latter part of the last Century many mammalian fossils were collected from the Corton beach and adjacent areas which are now in the Norwich Castle collection. There is a small series from Kessingland at Ipswich,

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o a

fi*

/O

o

FIG. 23

Representation of Cromer Forest Bed Series in the lower part of the Norfolk Cliffs. (Not to scale.) 1 Upper Chalk, 2 Weybourne Crag, 3 Lower Fresh Water Bed, 4 Estuarine Beds, 5 Upper Freshwater Bed, 6 Cromer Till, 7 Contorted Drift. The series varies in different parts of the coast.

originally part of Dr. Corner's collection. Examination of bones, etc. from Kessingland at York and in the Geological Survey Museums, revealed a condition more akin to fossils from Norwich Crag than those from the Forest Bed Series to which they were attributed. The Norwich Crag obviously exists below the Cromerian at this site and may have been exposed during the last Century.

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Cromerian M a m m a l i a T h e mammalian fauna of the Forest Beds is formidable, with more varieties of Proboscidae and Cervidae than in any later formation. Their study is complicated by the fact that a large proportion of fossils have been collected from the beach after storms so there is uncertainty from which horizon they were derived. Few o f t h o s e found in situ have any recorded data and the fact that other bones washed from the underlying Weybourne Crag, which has similar Villafranchian species, have been mixed up with the others makes the problem more confusing. For many years the large "Southern Elephant", Archidiskodon meridionalis, was regarded as first appearing in the Forest Bed but it has now been definitely established as having existed from the earliest Pleistocene, i.e. from the vanished pre-Red Crag Continental deposits destroyed by the incursion of the Red Crag Sea, its remains also occur in the Red and Norwich Crags and are particularly common in the Westleton Beds. It became extinct with the Cromer glaciation together with most of the Villafranchian deer, so its ränge in time is of the order of some two million years.

If it may be assumed that the numerous and varied beds which constitute the Forest Bed Series, some of which are channelled into older ones, are to be regarded as deposits laid down in a large river delta, perhaps some of the apparent difficulties raised by the seeming presence of animals of different periods supposedly having been found together are less difficult of Solution than has appeared.

However, the lack of accurate data regarding the site and bed from which the bones came is the greatest handicap in the study of the fauna.

One other problem is the difficulty of determining the relationship of odd limb and other skeletal remains of cervids with the imperfect skulls and antlers. T h e latter are fairly plentiful because each stag sheds his antlers annually, but generally only fragments have survived. Some portions of deer skulls occur consisting of the frontals, pedicles and sometimes with the antler bases attached. There are no associated skulls and mandibles and the latter are invariably incomplete though they often have some teeth. In the British Museum (Natural History) and the Norwich Castle Museum are numbers of limb bones varying from small to very large, and including at least two small deer and many large and giant species. One cannot know what Variation there may have been between sexes, which can be misleading.

Incomplete skulls of walrus and cetacean remains occur with remains of land fauna. T h e present ränge of both, particularly the former, has been much restricted owing to over killing by mankind. Tusks of walrus, Trichechus huxleyi, in a heavily mineralised condition occur in the Red Crag Basement Bed and there is at

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least one specimen at Ipswich which may be indigenous. Portions of a tusk f r o m the Westleton Beds at Holton, now at Ipswich, and unmineralised bones f r o m Aldeby at Norwich, record the continued presence of this marine m a m m a l t h r o u g h o u t the whole of the early Pleistocene. A n e n t this it is interesting to note that some AngloSaxon objects of archaeological importance are carved f r o m walrus ivory, implying that this material was readily available about a thousand years ago in the N o r t h Sea region.

Other marine vertebrates represented in the Cromerian are the narwhal, Monodon monoceros, now normally f o u n d between 70-80° N., and a variety of fishes such as Cod, Haddock, Sturgeon, Ray, etc. T h e r e are also n u m b e r s of freshwater species, perch, pike, carp, r u d d , tench, etc. Such a mixture seemingly supports the view that the Forest Bed Series owe their origin to deltaic conditions.

The Cromerian Terrestrial Fauna Elephants Archidiskodon meridionalis Palaeoloxodon antiquus Mammuthus primigenius

Horses Equas robustus (magmis) E. caballus fossilis?

Deer Megaceros verticornis M. dazvkinsi M. savini Cervus cf. elaphus Euctenoceros sedgwicki E. tetraceros E. ctenoides Dama nesti nesti D. clactoniana

Bovids Bison sp.

Rodents Trogontherium cuvieri Castor europaeus Arvicola (7 species) Sciurus vulgaris Insectivores Myogale moschata Sorex vulgaris S. pygmaeus Talpa europaea

Ovibos moschatus Caprovis savini Carnivores Ursus spelaeus U. ferox-fossilis V. savini = arctos-deningeri Canis lupus C. vulpes Gulo luscus Martes sylvaticus Machairodus sp.

Pig Sus scrofa

Elephants In n o o t h e r British geological period have so m a n y types of elephant existed and at least one author includes a f o u r t h species, Elephas trogontheri.

T h e fact is that t h e Elephantidae are at present the most confusing g r o u p of animals and it is considered t h a t the species should b e c o m e genera. A. Savin, who in a lifetime of collecting along t h e C r o m e r coast, amassed two large collections

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which are now at the British Museum (N.H.) and Norwich Castle, stated that if one typical elephant tooth was placed on a floor other teeth with varying characters could be arranged radially around it, and others placed between the radii linking up with slightly similar teeth.

Normally the remains of dead animals decay by natural processes and teeth are the most durable parts of a skeleton, unless the remains become buried soon after death they do not become fossil.

As a consequence teeth constitute the great majority of elephant fossils and in the absence of skulls are the means by which species are determined. This is by the pattern shown on the grinding surface and the number of laminae (plates), also by the thickness of the enamel of which the plates are composed (FIG. 24).

A

B

C FIG. 24

Representation of the pattern formed by wear on the functional surface of the molars of — A Archidiskodon meridionalis, B Palaeoloxodon antiquus and C Mammuthus primigenius.

A is the elephant of the Crag Series b u t it is associated with B and C in the Cromer Forest Bed. B is the only elephant of the Hoxnian but is associated with C in the Ipswichian in the lower and middle stages. C appears to be the only representative of the family in the late Ipswichian where it was very common. It became extinct in England at the end of the last interglacial.

The dentition of elephants is composed of three elements, the laminae consist of more or less flattened enamel tubes originating in the alveolus as a number of smaller tubes arranged laterally and growing together to form one plate, these are filled with dentine and are united by cementum which also Covers the whole tooth. Unlike

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other mammals elephants do not have a deciduous set of milk teeth which are shed and replaced within a short period. In elephants the first milk tooth composed of three or four plates, when largely worn out in use is replaced by number two with two or three additional plates, which in turn is succeeded by a third until the fourth milk tooth comes into use following the ejection of the stump of the third. Sometimes a stump is swallowed and its surface is modified and polished by the gastric juices. T h e true molars succeed each other in the same way: as each tooth is worn down by masticating coarse Vegetation, its successor is developing in the alveolus, the anterior laminae forming first the lengthening and uniting of the little tubes to build up each plate; thus the anterior portion of the second and third molars may cut the gum and become functional before the posterior portion is completely formed. When the third and last true molars come into use, one pair in each jaw, upper and lower, the life of the animal is limited by the duration of the teeth in use. These teeth, usually designated as R. Mä and L. Ms!, are immense compared with teeth of other mammals and in a large bull may be about eighteen inches long. In the mammoth the laminae are greatly compressed and exceed twenty in n u m b e r while the enamel is thinner than in other genera.

Skeletal remains of elephants cannot fail to be recognised because of their large size, for instance the femur of a large bull may be from five to six feet in length, but few are secured entire.

T h e facets by means of which the various limb bones articulate vary in form according to the species and are therefore sometimes useful in the determination of incomplete odd bones.

Giant Deer T h e remains of the numerous varieties of deer found in the Forest Bed Series are perhaps the most fascinating group of fossils of the period, particularly the Megaceridae (giant deer). T h e largest spread of antlers is in Megaceros verticornis which species had an extraordinarily broad palmation. Very few even partly complete antlers have been discovered, most are shed bases with a part of the brow tine which is easily distinguished from other species; this tine grows upward from the beam of the antler near the burr and turns forward and slightly downward then upward in a shallow horizontal S curve. M. dawkinsi has a short beam with a less expanded palmation and widely spaced broad based tines, the brow tine is variable and may be absent in young specimens.

M. savini has no palmation but the brow tine is expanded laterally.

Comb-antlered Deer Members of the Euctenoceridae are well represented in both the Crag and Forest Bed Series, the largest is Euctenoceros sedgwicki with many branched antlers the broken tines of which occur fairly

Suffolk Natural History, Vol. 15, Part 2 168 frequently and may be recognised by their undulating character (FIG. 25, 4a). The surface of the antlers in this group is smoother than in most deer, with shallow furrows andfissures.E. tetracer has a long slender beam with aflattenedsection and up to four long tines, according to the age of the animal. E. ctenoides known from a frontal with antler bases and part of another found near Mundesley by B. C. Belson. In this species the brow tine projects forward almost in line with the beam which is inclined backward, like Rucervus eldi the Asiatic swamp deer*, there i group of small projections at the junction of the beam and brow tine. The beam is slightlyflattenedvertically and rougher than in other mernbers of the family.

Red Deer

Several basal portions of antlers have been found which in later interglacials would without doubt be referred to the red deer, Cervus elaphus, but because nothing resembling the main d tinguishing feature of the species which is the terminal tines grouping to form a cup-like arrangement, the name C. elaphus included with doubt. It must be stated, however, that the upper parts of antlers of any species are very seldom found.

Earlier authors, unaware of the affinity of Cromerian deer with the Italian Vilafranchian fauna, adopted names for their specimens which are not valid. Cervus rectus Newton is based on a p and antler base with a combined length of 120 mm. which is a first year pricket of a small species, possibly Dama nesti nest antler attributed to C. etueriarium Crozet and Joubert is proba the same species. Other invalid species are C. carnutorum an C. polignacus which Azzaroli considers belong to Eucteno falconeri or E. sedgwicki, he also now believes C. obsc based on malformed antlers of Megaceros verticornis (pers communication).

Horses

The large equine teeth originally thought to belong to Equus stenonis are actually those of E. robustus (syn. magnus) Dr. A. T. Hopwood, but Professor A. Azzaroli is of the opinion that horses can only be accurately determined from mainly complete skulls, unfortunately no skull of E. robustus has so far been d covered and possibly the best existing specimen is the fragmentary mandible with one tooth missing, also part of the left premaxilary with two incisors probably of the same skull from Norwich Crag, Easton Bavents, now preserved in Ipswich Museum. Various separate teeth and limb bones from Cromerian deposits are in •The Deer of the Weybourne Crag and Forest Bed of Norfolk, 1953, pp.

73-76.

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collections, the smaller teeth have been named E. caballus fossilis because they resemble the teeth of modern horses but implying some difference due to their much greater age. The Variation in the dimensions of the equine long bones (metapodials) must in some instances be due to sexual differences.

Oxen Bovine remains are not common in the Cromerian but frontals with horncores exist to show that Bison bonasus was present during the Forest Bed period. One excellent specimen of a dorsal vertebra is in Norwich Castle.

Skulls with horncores of the musk ox, Ovibos moschatus are better represented in collections but other skeletal remains are rare.

Several skulls have been trawled from the North Sea bed where animal bones of many periods are known to occur, representing those occasions when the level of the sea was far lower than in our time.

Goat?

Caprovis savini is a genus created by E. T . Newton for a then unique horncore from Overstrand which is in the British Museum (N.H.) and has characteristics which make it difficult to decide if it was a sheep or a goat. This specimen is in remarkably good condition, but another example was detected by the writer in a box fĂźll of broken bones collected by the late J. E. Sainty of West Runton. This specimen had evidently been on the beach for some time and was much rolled. Its more robust character represents a more mature beast than Savin's specimen of which the sutures indicate an immature animal. One is from the left side and the other from the right but it is obvious two animals are represented.

No skeletal remains referable to this species have been detected.

Beavers A large variety of Beaver is represented in the Forest Beds and is known as Trogontherium cuvieri, as well as bones and teeth like those of the existing Castor europaeus. There is, however, another giant beaver in the Hoxnian interglacial, T. lydekkeri, it is from the Hoxne Lake Beds. Teeth of all these species are also recorded from Crag sands.

Pig Fossil remains of pigs seem to be very rare in later East Anglian deposits and they are not common in the Forest Beds, there is a largely complete skull of Sus scrofa in the Norwich Museum and an incomplete toothless mandible at Ipswich from Kessingland.

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Sabre Tooth There is a perfect canine from the Forest Bed in the British Museum (N.H.), the whereabouts of a mandible recorded from Kessingland is unknown. An incomplete canine from Norwich Crag of Covehithe is at Ipswich, it is determined as Ho?notherium sp. and for the Norfolk tooth Machaerodus crenatidens has been adopted with doubt. All the canine teeth British Machaerodus have now been examined, they are of one type which is minutely serrated on both edges. The specimen from Kents Cavern has coarse serrations however.

Bear A well preserved skull of a "cave bear" from the Forest Bed of Bacton, Norfolk, is preserved in the Norwich Castle Museum.

It was found in 1951.

Freshwater Mollusca According to B. W. Sparks the species of freshwater shells from one locality indicate transition from open water to marshy conditions with sluggish drainage Channels.* It has already been intimated that the Cromerian has been generally regarded as the first interglacial in Britain but there has not been discovered any evidence of a pre-Cromerian ice sheet.

The work of Dr. R. G. West and the Sub-Department of Quaternary Research at Cambridge, has proved there was a presumably earlier interglacial recorded in the pollens preserved in the silty layers of the Norwich Crag. These pollens show progressive changes from a cold flora to a temperate one and back to cool. As a non-specialist in this field of research one wonders if the pollen diagrams for the Norwich Crag and the Cromer Series are so dissimilar that there is no possibility that they may be in part, at least, contemporary. The writer believes that no pollen diagram for the whole of the Forest Bed Series can be satisfactorily worked out, the analyses having been done on samples from different localities and strata. Sparks has shown that the molluscan assemblage is indicative of marshy conditions with lagoons and the remains of fishes include both marine and freshwater species. This evidence is consistent with deposition in the delta of a large river but there is no evidence to indicate from which direction it flowed.

The series of Forest Bed deposits are varied with newer Channels formed in older beds in some localities. With the rapid construction of coastal defence works along the Norfolk coast, opportunities for solving the many problems are becoming fewer. The absence of any evidence of ice between the Norwich or Weybourne Crags •Phil. Trans, of the Royal Soc., vol. 246, pp. 197-199.

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and the Cromerian is a factor to be taken into consideration in any discussion on the Early Pleistocene in Britain.

The Hoxnian (Penultimate) Interglacial The Hoxnian Interglacial deposits invariably rest on, or in hollows of t h e Lowestoft Till, glaciers of L o w e s t o f t ice cut C h a n n e l s over one hundred feet deep into the Cromerian landscape which existed for a time as long narrow lakes. One of the most important of these exists as a remnant on the plateau at Hoxne with post Hoxnian Valleys formed on both sides. DĂźring the latter part of the 18th Century the lake clay was used for brickmaking, an industry which has continued until recent years at the same spot.

It was here the early stone implements of prehistoric man were first recognised by John Frere as the artifacts of men "who had not the use of metal". He also recorded (1794) the presence of huge bones which we now know must have been the remains of elephants, unfortunately none of these appear to have survived. It was only three years ago that a mechanical excavator broke up an elephant mandible of which one tooth and some of the fragments went to Ipswich Museum where a partial reconstruction was found possible by the writer, subsequently the other tooth was obtained. These remains are those of the "straight tusked" elephant, Palaeoloxodon antiquus and represent a fully mature cow of the only species so far found in Hoxnian deposits.

Mr. J. Reid Moir, who carried out various excavations at Hoxne in search of evidence of prehistoric man, thought that the Hoxne elephants must have been mammoths without any material evidence and in his published report also mistakenly included reindeer in the fauna. His evidence for this was a wrongly determined metatarsal of a red deer which in his lifetime had not been restored, the bone is too long and the straight shaft lacks the lateral expansion found in the same bone of reindeer.

Far too few bones have been preserved from this important site and these are mainly fragmentary, an exception is a pair of bones, radius and metacarpal, from the fore limb of a small variety of Red Deer found below the lake deposits lying on the Lowestoft Till.

The basal portion of an antler of a much larger deer was unearthed near the kiln of the brickyard which can only be matched with antlers of Cervus elaphus angulatus. Other fossils include teeth representing at least eight horses, one tooth and a limb bone of Bos or Bison, also one bone of pig. One of Moir's more interesting discoveries is the pedicle of a slain deer with a circular groove indicating an attempt to cut off the antler by Acheulean man a quarter of a million years ago. It was recorded by Frere that the Acheulean flint artifacts were so numerous that baskets-full were used to fill ruts in the road.

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Hoxne has been selected as the type site of the penultimate interglacial and the site is remarkable because the deposits which were originally in a Valley are now situated on the plateau between the Valleys of the River Dove on the west and Gold Brook on the east. In the Ipswich area there are high level elongated patches of brickearth between Kesgrave and Purdis Farm, one of these produced numbers of Acheulean flint artifacts similar to those from Hoxne, both occur above the Lowestoft Till. High level gravels at Dovercourt with Acheulean implements presumably belong to the same period and indicate a similar reduction of the level of the Hoxnian land surface between that period and the Ipswichian interglacial (FIG. 25).

F I G . 25 Section through the Hoxne plateau showing the post Hoxnian Valleys representing a great reduction of the ground level during the past quarter million years. (Not to scale.) 1 Hoxnian Lake Beds, 2 Lowestoft Till, 3 Sand.

Marks Tey In eastern Essex at the Marks Tey Brickworks the upper part of over a hundred feet of laminated clay has long been utilised for brick making. T h i s laminated deposit has yielded fish remains, Salmo sp., probably trout, and pollen analysis, by Dr. Chas. T u r n e r of Cambridge, has shown that the clay Alling an ice cut Channel is an accumulation formed during the latter part of the Hoxnian interglacial. T h e laminae undoubtedly record the annual wastage from a higher landscape over many years of climatic deterioration and accounts for the loss of the Lowestoft Till in that area as a comparison of the mineral grains would doubtless prove.

Clacton On the Essex Coast there is the Hoxnian "Elephant Bed" of Hazzledine Warren at Clacton and on the foreshore of Jaywick.

These deposits of the ancient Thames which originally flowed via Ilford, Clacton, and Walton-on-Naze contain a primitive industry of polygonal flint cores and coarse flint flakes which preceded the

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Acheulean industry. The Hippopotamus Bed at East Mersey, near the Church, is rieh in animal remains, particularly Bison of whieh part of a skull is in The Institute of Archaeology, London.

Other members of the fauna include lion (or tiger), Palaeoloxodon antiquus (the only species known from the Hoxnian) and the Giant Deer, Megaceros giganteus. This site also lies on the line of the old Thames but has not yet produced flint artifacts or reeeived so much attention as the Clacton deposits.

Some bones from a former exposure at Walton-on-Naze are in the Manchester Museum.

The mammalian fauna of the Clacton Elephant Bed is given by H. Warren in the Quarterly Journal of the Geological Society,

Elephas antiquus—(Palaeoloxodon) Equus caballus

Felis leo v. spelaea—(Panthera) Hippopotamus amphibius Rhinoceros megarhinus R. leptorhinus Owen = (hemitaechus Falc.)

Ursus sp.

Perca fluvatilis Esox lucius Crayfish?

Microtus agrestoides?

The Clacton fallow deer, originally named C. browni in honour of John Brown of Stanway, a noted geologist of the last Century, seems to have become extinet with the oncoming of the Gipping glaciation and our existing fallow deer is a recent introduetion.

Antlers of the extinet variety are of great size measuring from three to live inches in circumference above the burr and a total length of about thirty inches.

St. Ives Within the past few years representatives of the Clacton fauna have been found near St. Ives in pits worked by Inns & Co. and the St. Ives Sand & Gravel Co., in the Galley Hill pits, Huntingdonshire. Numerous fragments of antlers of Dama clactoniana have been found in association with Palaeoloxodon antiquus, the narrow nosed rhinoceros Coelodonta hemitaechus, Bison priscus, Megaceros giganteus, Cervus elaphus and Ursus spelaea.

The deposits from which the bones are obtained were evidently laid down by the ancient River Ouse and it is certain that there are beds representing two periods, for remains of mammoth and reindeer cannot come from the same horizon as the fauna outlined above, they belong to the late Pleistocene faunas of the Ipswichian in the Orwell-Gipping and Waveney Valleys. Unfortunately the mammaliferous levels in gravel workings are usually below the water

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table so there is no means of determining the exact level in which bones occur. An attempt to explore flooded gravel pits by the Ipswich Sub-Aqua Club proved fruitless because the disturbance of silt prevented anything from being seen.

So far there are no records to hand of any flora or molluscan fauna from the St. Ives area but E. M. Reid and M. E. J. Chandler listed no fewer than 137 plants from the Clacton Beds. Eightytwo species of non-marine mollusca were determined by Ä. S. Kennard and B. B. Woodward who regarded this as the longest list from any English Pleistocene site. This is now rivalled by the list from the Ipswichian Bobbitshole site.

Deposits of the Great (Hoxnian) Interglacial are not well exposed in Suffolk but some sites are known, such as the former brickfield at St. Cross South Elmham, Riverside Road, Ipswich, where mammaliferous gravel (with Bison) occurs between the Gipping and Lowestoft Tills. The former Valley Brickfield at Foxhall Road, Ipswich has now an Engineering Works thereon.

West Suffolk, Worlington There are few recorded mammaliferous sites in West Suffolk of Hoxnian age but there are some which are probably of this period, some of which were revealed by the construction of railways during the last Century, others are implied by scanty but possibly significant evidence. One is the railway cutting at Worlington about two miles from Mildenhall made in 1887 when teeth, etc. of Palaeoloxodon antiquus, Hippopotamus amphibius, Rhinoceros sp., and lion or tiger of which only the teeth were preserved. These remains are at Ipswich. Another site is based on a brief reference to the discovery of bones during the making of the cutting through Norton Wood*, about a mile from Elmswell, but there is no record of any specific identifications. More recently a large portion of an elephant thigh bone was found at Thurston, two miles further west, but the exact site is not recorded. The bone is massive enough to have belonged to a large bull of P. antiquus. These adjacent sites between 170 and 200 feet O.D. are most probably of similar age, and Hoxnian to boot. It is unfortunate that none of the original fossils are available for study but their height above sea level is very significant.

Gt. Waldingfield A well bore record from Gt. Waldingfield gives twenty-five feet of clay (Ptill or brickearth), above six feet of sand and ten feet of shell mud. The names of the following mollusca are listed but possibly the list is far from complete:— •Suffolk Inst, of Archaeology and Natural History, vol. 2.

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Bithynia sp., Cyclas sp., Limnea sp., and Planorbis sp., several species of the last two genera are to be expected, fragments of wood are also mentioned. This site is at about the same level as Norton Wood and Thurston which implies the deposits are about the same age. As a well between four and five hundred yards away is in chalk at thirty-five feet it appears the shell mud lies in a hollow in the chalk.

Westley In this parish to the west of Bury St. Edmunds there are pockets of Brickearth in the chalk from which Acheulean flint artifacts were obtained during the last Century. Bones and teeth of elephants, etc. were also discovered, but most important was a portion of a cranium of prehistoric man, one of the very few human fossils found in the County. Unfortunately, this is too small to give any indication of which of the early races of man it belonged to. One would have assumed it to belong to the Acheulean race who left so many of their stone implements but Dr. K. P. Oakley, of the British Museum (N.H.), formed the opinion, based on a fluorine test, that it is not of that period.

Thorndon Incomplete bones of elephant and other large animals from an unrecorded site at Thorndon are, to judge from the elevation, and the position in the Dove Valley system, in all probability of Hoxnian age.

It is of interest to note that the earliest English record of fossil bones dates from the reign of King Richard the first, according to Ralphe the Monk of Coggeshall. This refers to the discovery at Erdulphness (Walton-on-Naze) of "two teeth of a certain Giant, of such huge bignesse, that two hundred such teeth as men have now a daies might be cut from them. These I saw at Coggeshall".

Summary of the Hoxnian interglacial It is obvious that the remnants of lake and river deposits of this period constitute positive proof of considerable topographic changes, this is also indicated by the separate outliers of Lowestoft Till which is very patchy around Ipswich. The buried C h a n n e l s cut by the Lowestoft ice sheet must have been glacial lakes during the early stages of the following interglacial, but some like the one at Ipswich were silted up during the retreat stages of the ice sheet.

At Marks Tey, the C h a n n e l , which retains some Lowestoft Till in the bottom, cut by ice below the present Roman River, was for some unknown reason not silted up until after the middle of the temperate period with clay derived from the reduction of the boulder clay

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capped plateau. The examination of samples from bore holes at Marks Tey by Dr. Turner, one of which penetrated one hundred and twenty feet, proved the lower layers to be much the same age as the Hoxne Lake bed, but the upper part, the laminated clay used in the brickyard, contained organic matter unlike the varved clays deposited by melt water from a retreating ice sheet. The fossil pollens revealed increasingly wetter and colder conditions during the latter part of the interglacial. The upper laminae may represent the annual amount of silt carried down stream, or perhaps record the periods of exceptional rainfall.

The series of mammaliferous deposits along the course of the former Thames, which may have then been a tributary of the Rhine, is also an indication of geographic changes and we can have no idea of what an East Anglian coastline might have been like a quarter of a million years ago.

The Ipswichian (Ultimate) Interglacial The term Ipswichian was proposed for this phase of the late Pleistocene by Dr. R. G. West on the results of his pollen analysis of the lake deposits at Bobbitshole and the examination of the very rieh non-marine molluscan assemblage by B. W. Sparks. For the first time the land and freshwater shells were studied in relation to the succession of changes in the flora, from the same samples. The Bobbitshole lake beds were discovered by the writer as a result of the policy of the Curator of the Ipswich Museum, Mr. Guy Maynard, who encouraged the examination of temporary sections for both archaeological and geological evidence. This involved Walking through some miles of trenches in the Ipswich District and resulted in the discovery in the area south and west of Ipswich Station of evidence of occupation, from the Levallois Stone Age industry, to the Neolithic, Early Iron Age and Roman. Traces of the Levallois were found in the Stutton Brickearth of the same period.

Bobbitshole is in the Valley of Belstead Brook, three quarters of a mile upstream from Bourne Bridge and just above the point to which ordinary tides flowed before the construction of the railway embankment about 1840. It was owing to the chance that this site was selected for the construction of new sewage disposal plant that this series of Valley bottom deposits was revealed where no commercial excavations were ever likely to be made.

Marshy meadows and reed beds mark the area of the former tidal creek between low banks which are still traceable. Belstead Brook has cut down into the surface of the chalk which occurs at, or a little above Ordnance Datum and, contrary to the one inch geological map, the alluvium lies in a hollow from which the Lower London Tertiaries (Thanet, Oldhaven, Reading Beds, and London

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Clay) were removed during an earlier stage in the formation of the valley. A hillwash, mainly of redeposited loess, blankets the lower part of the southern slope. Its character was revealed in two trenches from Wherstead Road to the site of the plant, in the excavation of these great numbers of waste flint flakes were thrown out proving that the outcrop of the Bullhead Bed flints esposed by the tides had been the source of flint for the artifacts of prehistoric hunters. Unfortunately, no implements indicative of any known industry were found. While by far the greater number of flints used were from the basement (Bullhead) Bed of the Thanet some were an unusual local white veined flint of tabular form from the Chalk or of a speckled flint. An indication of the early formation of the hillwash was seen in the side of one trench in a very much decayed tooth of mammoth which had been badly broken by the excavator. Near Belstead House Residential College the Brook flows in a C h a n n e l cut down into the Gipping Till and some of this Till was exposed in the southern hillslope at about twenty-five feet, the surface was very irregulär and was buried below some sixteen feet of loess. This seemingly implies that the valley was choked with tili at the end of the Gipping glaciation and then reformed only to be partly filled with the wind blown dust (loess). Again the stream cut down only to receive the Bobbitshole lake deposits during the first part of the Ipswichian interglacial, this is proved by the pollen analysis.

In the lowermost excavation at the bottom of the valley, below detrital mud, a thick bed of loess, grey in colour owing to its Situation below the watertable where reduction of iron Compounds has occurred, presumably lies in a hollow in the chalk. An attempt to ascertain its thickness was frustrated by the saturated nature of the deposit which impeded the penetration of the boring tool.

The loess above the watertable is yellowish when dry but dull buff and clay-like when damp, when rubbed between the fingers it feels smooth like talcum powder.

The stratigraphy at Bobbitshole follows:— Upper excavation Fluvio-glacial gravel and sand with rafts of loess.

River terrace gravel with m a m m o t h , bison, etc.

T h i n marginal lake zone of sand with Emys orbicularis and fragments of m a m m a l bones (due to fluctuations of lake level).

Buff loess, bored to 16'.

Gipping Till.

Lowest excavation Fluvio-glacial gravel and sand.

Mammaliferous river gravel.

Calcareous m a r s h clay, ironstained with m u c h race, a b u n d a n t mollusca, bones of m a m m o t h , bison, red deer and driftwood.

Peaty detrital m u d with a b u n d a n t twigs and other driftwood, very abundant land and freshwater shells, microtine, amphibian, fish and beetle remains.

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Loess (grey).

Unstratified gravel (gravelly tili), cutting out the lake beds at the north end of the section. A stony tili of the last glaciation confined to the Valley bottom.

Owing to the modern use of mechanical excavators, opportunities for collecting fossil bones are fewer than when work was done by pick and shovel, then, when a fossil was exposed it could often be removed more or less complete. Today bones or teeth are seldom seen and are usually broken, only a few fragments and fewer partly complete bones were recovered from Bobbitshole lake beds and these were mainly from spoil heaps. These represent Mammuthus primigenius, Bison, Cervus elaphus and Castor europaeus also Emys orbicularis, the south European pond tortoise. T h e teeth of shrews, voles and other remains of small mammals with fish, amphibians and beetles were recovered while washing samples of the deposits through a fine sieve to secure small shells. T h e smgle bone of beaver is an exceptional find and may be an indication of damming the stream by beavers.

T h e Ipswichian fauna is much better represented in the Stoke Hill Beds at the southern end of the Ipswich Railway Tunnel T h e y were first revealed about the middle of the last Century when the railway was constructed, subsequently other investigations were made. See Part 2 of these Contributions. pp. 41-42 (Trans Suffolk Nat. Soc. Vol. 13, Pt. 5, 1967.)

Stoke Hill, Ipswich It was at Stoke Hill that remains of the pond tortoise were first recorded in East Anglia but it was only in recent years when the significance of this reptile as an indicator of a warm climate in Pleistocene deposits was recognised. Only in a climate like that of present day southern Europe can the creature breed. Bobbitshole is the second site in the Ipswich area from which it has been obtained. Subsequently more fragments of Emys were discovered in association with fossils of mammoth and red deer by John Norman at Stutton. On a visit to University Museum, Oxford, the writer was shown a cabinet of miscellaneous fossils which had belonged to Sir Charles Lyell, one of the pioneers of Geology, in it several fragmentary specimens of Emys from sundry sites were discovered, unfortunately there were no data with any of them.

Their condition varied and it is possible that one of these may have been obtained from the Stoke railway cutting.

Perhaps it is not unreasonable to infer that Emys was fairly common in East Suffolk during the middle of the Ipswichian interglacial. Unfortunately the plates of the carapace, the plastron and the h m b bones are quite small and are easily overlooked, or if seen are perhaps thought to be unimportant; as was once said by one

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noted Pleistocene specialist when shown some of the bones. At Stutton Emys is associated with Corbicula flumenalis, a mollusc not now living nearer than the River Nile and is therefore another pointer to warm climatic conditions.

In Denmark more or less complete specimens of Emys orbicularis have been discovered in peat deposits.

North Sea Bed Of the quantities of bones which litter the North Sea Bed few are brought ashore as fishermen tend to dump them in unprofitable areas.

One important and interesting discovery is the mammoth skull trawled up thirty miles east of Lowestoft, which the writer found in the garden of Mr. Long at Pakefield in 1953 and was presented to Ipswich Museum by him. Had it remained exposed to the weather, frost would have reduced it to fragments. Although elephants are now fond of water, swimming is not one of their accomplishments so it cannot be supposed this beast swam to the spot where the skull was found. It is therefore most highly probable that the present sea floor was dry land when this elephant lived during the Ipswichian interglacial. The oblique angle of the grinding surface of the teeth match teeth with a similar angle in Stoke Hill Beds mammoths (Mammuthus primigenius).

Some phosphatised elephant teeth from the sea bed in the Natural History Museum, Colchester, resemble sub-Red Crag fossils but the types are late Pleistocene. At Ipswich, a mandible of Palaeoloxodon antiquus of Cromerian age is preserved which was trawled up off Shingle Street about 1925. A pelvic bone of rhinoceros was found near the Cork Lightship and a bone harpoon point of the Magiemose food gatherers came from a mass of moorlog on the Ower and Leman Banks.

Off Southwold numerous bones, mostly of Crag age, have been retrieved from the sea bed and others are cast ashore at Walberswick during storms.

Bovine bones from the Stony Banks off Walton-on-Naze may perhaps be of Hoxnian age.

Across the North Sea quantities of bones have been dredged up for scientific research.

Because the entire mammoth bodies found frozen in Siberia have become so well known there has been a widely accepted misconception that the woolly elephant and the woolly rhinoceros lived together in extremely cold conditions, the bodies of both having been discovered in a frozen S t a t e . The fact that such large herbivores need great quantities of Vegetation on which to subsist

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has been largely ignored, and such abundant Vegetation is most unlikely to have flourished in extremely cold conditions, still less so in our region when the country was blanketed under two or three hundred feet of ice. Today the young of elephants are born hairy but lose the hair except for a few very thick wire-like hairs at the tip of the tail and as no other extinct species of elephant has ever been discovered frozen, it cannot be known if they were equally as hairy as the mammoth. T h e teeth of mammoths exhibit some Variation in structure which some specialists consider enough for division into species. It is well known, however, that many living animals widely distributed in different environments frequently exhibit marked differences and are regarded as variants, or sub-species.

T h e r e seems to be a similar misconception anent prehistoric man who could not have existed during the periods of extreme cold.

Evidence of bones in cave floors show that stone age hunters in the latter part of the Ipswichian co-existed with the reindeer, a tundra species. East Anglia, and SufFolk in particular, has yielded great numbers of flint artifacts made by Mousterian, Levallois and some of Solutrian hunters. It is unfortunate that collectors of these implements during the last Century did not record the associated mammals found in the same deposits. Now it appears that the few Quaternary palaeontologists tend to ignore relevant material evidence outside their speciality. In East Suffolk Levallois artifacts are associated with the mammoth-red deer fauna and Solutrian with mammoth-reindeer.

As the Gipping ice sheets retreated and the climate ameliorated, plant life began to spread northward and as warmer conditions prevailed the animals followed, then the hunters appeared. At the same time the sea level was rising and river Valleys aggraded.

After the climatic maximum this process was reversed and another " I c e Age" followed, accompanied by a reduction of sea level owing to the amount of water locked in the expanded polar ice cap. It is during the latter part of an interglacial, as the sea level is lowered, that the lowest river gravels with the mammoth-reindeer fauna are deposited which are at present below the watertable and buried by recent flood piain deposits in our Valleys.

T h e only evidence of climatic changes during the Ipswichian Interglacial available to early workers were fossils of animals living normally in mild, warm, or cool (tundra) conditions, with indications of topographical features suggested by the preponderance of grazing or browsing animals. T h e science of pollen analysis has provided a more positive means by which the gradual changes in the flora from cool to warm and back to cool may be detected.

Likewise a detailed study of the land and freshwater shells of a site like Bobbitshole, such as that by B. W. Sparks, gives a good deal of information with regard to the topography, because some species

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dwell only in certain types of environment, fen, sluggish or fast flowing streams, ponds or lakes, open country or woodland. Small mammals, like field mice and voles, are useful because of their relatively short lives: they reflect evolutionary changes from one temperate period to another. Remains of small mammals, like the teeth of shrews, mice, voles, etc. are seldom if ever seen and in general are only collected if and when their presence is suspected.

Such fossils are secured by a tedious method of washing quantities of a deposit through a fine sieve and then searching through such debris as may be retained. One is fortunate if more than a few teeth occur in half a dozen or more sievings. Luckily a few were found during the washing for minute species of Bobbitshole mollusca; the most interesting find was a mandible of a shrew.

A deep excavation near the brook at Bobbitshole, a short distance downstream, had no trace of the detrital mud, the lowermost lake bed, and since there is evidence of the presence of beavers there is the possibility that they constructed a dam and so formed a pool in which to make their lodges. If this were so it might account for the great quantity of twigs, etc. in this deposit. In any case the fossil wood, twigs and certain snails prove that trees were present near the lake shore.

The formation of a beaver dam would cause the formation of marsh upstream of the resulting pool and supporting evidence of this conclusion may be seen in the great number of marsh-loving mollusca in the deposits.

Only one bone of red deer, a radius, was found but it's importance lies in the fact that it had been split longitudinally in the manner of prehistoric man in order to extract the marrow, it is therefore an indication of prehistoric hunters in the area. This is confirmed by the discovery of flint artifacts of the Levallois industry in the Stoke Hill Beds, where red deer bones occur with greater frequency.

Bobbitshole Mollusca The Bobbitshole shells are of particular interest and are comparable in the number of species with other richly mollusciferous sites ranging from the Cromerian of West Runton, the Hoxnian of Clacton and Swanscombe, and the Ipswichian of Cambridge and Stutton. About half are aquatic and the numbers of these greatly exceed those of land species, with over half living in Suffolk at the present time. Two species are extinct in this country, Belgrandia marginata and Vallonia pulchella var. enniensis. Over 2,000 specimens of the former were collected and its habitat seems to be Springs of which there must have been a number in the Valley enierging from the base of the Red Crag, Vallonia is a marsh

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dweller and its earliest record in British stratigraphy is from the Red Crag of Bawdsey.

T h e painstaking work of B. W. Sparks involved the examination of nearly 40,000 shells varying in size from about the size of a pin head to just over an inch in length, by far the greater number were small. Of Valvata cristata over 12,500 were counted compared with 170 Lymtiea palustris, of which species the shells were much larger than those living in the region at present. Over 6,000 Bithynia tentaculata were noted, but it is considered a much greater number might have been obtained from a larger sample. The opercula were extremely numerous in both the detritus bed and the marsh clay, in size they were similar to those of snails now living in the Gipping Valley.

Amongst the rarer species is the slug Agriolimax caruanae, which was first recorded from Malta and is known from but a few localities in this country. This interesting record is included with some doubt by Sparks because A. agrestis has a somewhat similar shell.

Only Single examples of some shells were recorded, but it must be noted that the specimens were from a four-inch diameter core nine-and-a-half feet long. This was used to determine how many and which species occurred in each pollen zone; this being the first time such a tedious task has been attempted. Systematic collecting from each zone would obviously yield a very different Statistical table. Specimens collected by the late A. G. Davis, M Kearney, and the writer, included a few species additional to those in Sparks list. Together the lists record about eighty species and in order that all are listed in these contributions, Davis' list, which appeared in the Trans. Suffolk Nat. Soc. Vol. 9 , p p . 110-114, is given below:— P—Peat MC—Marsh Clay. C—Common. Ab—Abundant.

P MC P MC Valvata

cristata

C

V. piscinalis ...... 15 V. macrostoma 1 Pomatias elegans ......— Bithynia tentaculata Ab Belgrandia marginata 33 Carychium tridentatum 2 C. minitnum 24 Lymnea truncatula 8 L. palustris Ab L.peregra C Myxas glutinosa 23 Physa hypnorum 1 Planorbis carinatus C P vortex — P. planorbis 1 P vorticulus C

Ab

Unio tumidus

C 45 1 Ab C 6 C C 75 C 33 20 89 36 3 C

Succmea pfeifen Cochhcopalubnca Truncatelhna cyhndnca Vertico antivertigo V. mouhnsiana V. angustior Pupillamuscorum Acanthinula aculeata V. pulchella var. enmensis V costata Claus,ha bidentata C. lammata Helicodonta obvoluta Arianta arbustorum Helix nemorahs

....

—

2

2S 1 — C 17 5 — —

C 04 1 Ab öO AD / i

2S — — — — —

v. »' S =

J

3

0

GEOLOGICAL HISTORY

P. leusostoma P. albus P. crista Segmentina nitida S. complanatus Acroloxus lacustris Euconulus fulvus Vitrea cristalina Oxychilus cellarius Retinella radiatula Zonitoides tiitidus Vitrina pellucida Limax spp.

L. modioliformis Unio pictorum

P MC 17 C — 1 40 1 27 65 80 C — 6 — 1 — 1 1 50 6 12 — 1 77 Ab — IS 1 —

c 5

Hygromia hispida H. libertus Punctum pygmaeum Discus rotundatus Ariern sp Succinea oblonga Pindium amnicum P. pulchellum P. obtusale P. nitidum P. casertanum P. milium P. moitessienanum P. personatum Sphaertum corneum

183 P MC 3 C — 9 2 15 — 14 — 3 4 40 10 C 6 31 4 2 — 16 4 20 — 4 4 14 — 12 C C

Helicodonta has not been recorded previously from the county either recent or fossil and its presence in the deposit is due to flooding of woodland, it is known from Cambridge. Pomatias is now rare in SufFolk and found only in chalky areas, locally it could have had a habitat on very chalky Gipping Till. Helix nemoralis was probably more common than is implied in the list, the shell is fragile in a fossil condition the whorls tending to separate: there was a tendency to pick Up only reasonably well preserved specimens from spoil heaps where many fragments could be seen.

The paper by Sparks on Bobbitshole Interglacial Beds, Ipswich, is given in the Trans. Roy. Soc. (Vol. 241, pp. 33-44), it lists the number of determinate specimens from twenty-five zones, indicated by the percentages of various pollen groups. There are three groups, one, of the most tolerant species over a wide ränge of climatic Variation, c o n s t i t u t i n g a b o u t 9 7 % at t h e b o t t o m of t h e

section, diminishing to 50% at the top: group two, the less tolerant forms, varies from 2% below and 33% in the middle of the section and reduces in numbers rapidly toward the top. Group three, the least tolerant, are not represented in the lowermost sections and do not become common, 26%, until the maximum of group two, then diminishes in numbers to 14%, corresponding to a second maximum of group one, followed by an increase in numbers at the top of the section. This reduction in the number of species may represent a period of climatic deterioration to which those molluscs intolerant of unfavourable conditions would respond.

Bobbitshole Flora The results of the investigation (Pollen Analysis) by Dr. R. G. West is given in the same volume of the Trans. Roy. Soc. (pp. 1-31).

At Bobbitshole the pollens and other plant remains are those of the first half of an interglacial which corresponds with the pollen zones b, c, d, a n d / o f the Eemian (last interglacial of N.W. Europe which show a transition from Birch to Pine and then to a mixed Oak

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forest). The abundance of aquatic Vegetation indicates changes from open water to reed swamp and then to marsh, just the types of habitat indicated by the mollusca had there been no pollen to confirm it. Tree pollens give a general indication of the character of the region, in zone b, birch, pine and juniper are represented but evidently not as abundant as in zone c. In zone d, birch begins to decline, elm appears and with the pine begins to increase and becomes dominant in zone e, where oak begins to become common and in zone / is dominant and is associated with hazel. Over seventy species are included in the flora of Bobbitshole.

Acer cf. monspessulanum Ajuga cf. reptans Betula pubescens or B. verrucosa Carex acutiformis C. riparia C. rostrata C. sp.

Cladium mariscus Cornus sanguinea Eupatorium cannabinum Hydrocharis morsus-ranae Labiatae sp.

Lycopus europaeus Moehringia cf. trinervia Myriophyllum spicatum or M. verticillatum Nuphar luteum Nymphaea alba Oenanthe aquatica Potamogeton natans P. acutifolius P. cf. densus P. berchtoldii P. cf. pusillus P. cf. perfoliatus P. trichoides Rubus fruticosus Sagitarius sagittifolia Schoenoplectus lacrustus Solanum dulcamara Stachys sp.

Teucrium scordrum Thalictrum flavum Urtica dioica Zannichellia palustris

Alisma plantago-aquatica Betula cf. nana Berula erecta Bidens cernuus B. tripartitus Ceratophyllum demersum Chenopodium album C. polysphaerum Composite sp.

Crataegus sp.

Hippuris vulgaris Hypericum cf. tetrapterum Lemna cf. minor Mentha aquatica Myosoton aquaticum Nasturtium microphyllum Najas flexilis N. marina N. minor Polygonum cf. lapathifolium Prunus spinosa Ranunculus acris R. celeratus R. cf. lingua R. parvifloruss R. sp.

R.-Batrachium Rumex cf. conglomeratus R. maritimus R. repens R. sceleratus Sparganium angustifolium S. ramosum S. minimum S. simplex Verbena officinalis Characeae

Salvinia natans is not included in this list but West records it as becoming common in the upper part of zone d.

Dr. West remarked on the lower beds being below present sea level but failed to comment on the deposits of peat with abundant hazel nuts which dredging has shown to be ten feet thick below the bed of the Orwell Estuary. (One shell of hazel nut was found in the detrital mud at Bobbitshole.) Teeth and bones of red deer,

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mammoth, rhinoceros, urus, etc. were also brought up in the dredgings. An investigation of the submerged beds, is needed to establish their relationship to the Bobbitshole deposits.

Stutton Brickearth and Stour Valley After Hoxne brickyard, Stutton Cliff and former brickfield is perhaps one of the earliest Pleistocene deposits to receive attention because of its assemblage of non-marine shells with numerous Corbicula fluminalis*, a genus of mollusc not now found living nearer than the River Nile.

T h e shells occur in local patches in the Stutton brickearth and in two levels separated by a Stratum of more or less ferruginous gravel wherein a much crushed mammoth tusk was observed in 1948.

Parts of the Stutton Brickearth are mammaliferous and Observation has shown that the mammoth, Mammuthus primigenius, is generally confined to the exposures on the foreshore and lower part of the cliff. T h e fossil bones and teeth attracted little attention until about 1940, when J. Reid Moir moved to Fiatford and began an investigation of the flint artifacts found on the shore. He mistakenly thought these were derived from the brickearth and it was not until after his death in 1942 that it was established they occurred only in the subsoil at the top of the cliff and were Neolithic in origin.

It was subsequently found that the indigenous artifacts belonged to the Levallois industry and a rare discovery of exceptional interest was made by instalments between 1949 and 1962. It began when the writer saw part of a radius of a red deer on the shore in 1949, part of which was unusually glossy. In 1955, F. W. Simpson found portions of the shaft of a deer radius which had a very high gloss on the anterior face and this by a remarkable coincidence was found to fit the broken edge of the fragment found five years before.

It is even more remarkable that John Norman picked up the upper termination of a deer radius in 1962, of the same bone first noticed thirteen years previously. It is impossible to say how many times the tides had covered the place on the beach. T h e glossy condition matches that on deer bones used at the present time to burnish leather, in particular riding boots. Obviously the bone was in all probability used in the preparation of skins by Levallois man, or, more likely, woman. It was subsequently learned that the major portion of a similar bone, this time of Dama clactoniana, had been discovered in the Clacton Elephant Bed proving that long bones of deer had been used for a similar purpose a quarter of a million years ago.

At Stutton the late Day Kimball found there were some shells present in the upper bed only and vice versa, the gravel bed separ*Phil. Trans, of the Royal Soc. 1848, T h e Crag Mollusca. Searles V. Wood.

Vol. I I , p. 103.

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ating the lower and upper shell beds suggests some temporary change in the deposition by the ancient Stour. So far remains of the straight tusked elephant, Palaeoloxodcm antiquus, appear to be in the upper part of the brickearth, the remains of a tibia were taken only three or four feet from the surface. No human fossils are so far recorded.

Harkstead The Stutton Brickearth appears to occupy a Channel in the London clay and presumably became frozen to a considerable depth when it expanded laterally and the bedding of the London Clay became distorted (PLATE 9). Across Holbrook Bay it is masked by the London Clay cliff at Harkstead where erosion is rapid owing to the effect of the westerly winds over the wide Stour estuary. In recent years the south-easterly end of the cliff has been eroded exposing the brickearth behind and large patches of the marginal stony brickearth have appeared along the top of the cliff. The foreshore off the end of the cliff has proved rieh in mammalian bones, including a number from the skeleton of a young cow mammoth mixed with teeth and bones of two Bison: adhering to one bone was an incisor of a vole. In the same area was an uneut first milk tooth of an elephant foetus and incomplete teeth of a year old animal. Red deer have also been recorded from this site.

On one occasion at the water's edge at an exceptionally low spring tide, the ends of a pair of tusks of a part grown elephant were projecting vertically from the mud. Bones seen in the brickearth of the cliff where the London Clay has been washed away have invariably been crushed and indeterminate, evidence of the pressure of ice. Similarly, evidence of great pressure occurs on the Essex shore at Wrabness Cliff where brickearth has been forced along the jointing in the London Clay.

Brundon Upstream along the Stour, at Brundon, Sudbury, a gravel knoll was excavated for gravel, it was a remnant of a river terrace of which few can be recognised in this glaciated region. The fauna, including Corbicula fluminalis, is similar to that at Harkstead and Stutton. One discovery at Brundon was remarkable; it consisted of a pair of enormous tusks of Palaeoloxoilon antiquus about ten inches in diameter. They were found half way down the section and the right tusk had snapped half way along its length, the termination of these tusks were worn down and bevelled at an angle showing that the aged beast had for years been in the habit of resting its tusks on the ground because of their great weight. In this way the tusks were reduced in length by constant wear.

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Unfortunately, the weight of superincumbent gravel combined with the action of percolating water had caused deterioration of the ivory and although they were encased in plaster and removed to Ipswich Museum it was beyond the resources of the laboratory at that time to preserve them. Other remains of a very large elephant preceded the discovery of the tusks as the gravel working proceeded westward and it is thought, had the animal faced east, many of the bones might have been recovered.

The Brundon pit was worked by hand and it was for this reason that so many mammalian remains were preserved and when the workman attacked the elephant skull he either did not recognise it, or failed to notify the foreman and it is for this reason that only the palate with the stumps of the upper molars was preserved. It is thought that the very old bull probably went to the river to drink.

There his strength gave way and he feil with his weight on the right tusk which snapped. He died on the spot where the skeleton was buried by sand and gravel transported by floods one hundred thousand years ago. It is only when remains of animals are quickly buried that they become preserved in deposits of lakes and rivers.

DĂźring the 1930s a broken skull of the same species of elephant was found partly embedded in a layer of silt with Corbicula and other shells. The top of the skull had been broken off and was discovered inverted above the partly crushed mandible. The four molars, one lacking a few posterior plates, are the only complete set of third molars in Ipswich Museum. Brundon pit is also notable for the number of Mousterian and Levallois flint artifacts, one flint flake was lying on a mammoth tusk.

It was from the Brundon gravels that the first portion of an antler of the large variety of red deer, Cervus elaphus angulatus, was recorded but the finest specimen is from Stutton where a nearly complete antler was found in the cliff, one terminal tine is missing.

Reid Moir was found to have collected the occipital portion of the skull and the writer chanced to find the brow tine on the beach.

This fine specimen was presented to the Museum by Sir Clavering Fison.

Both Bos primigenius and Bison bonasus occur at Brundon and in the Orwell valley, but only Bison has so far been recorded from Stutton.

An almost complete skull of a female Megaceros giganteus in a crushed condition was found in the gravel. Fortunately it was possible largely to restore the specimen, but only a broken brow tine has been found at Stutton.

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Dr. A. Tindel Hopwood listed the following mammals from Brundon*, which is similar to that from Stutton, Harkstead and Wrabness.

Canis lupus Ursus spelaeus Panthera leo Equus caballus Rhinoceros (hemitaechus) Cervus elaphus

(Cervus elaphus angulatus) Megaceros hibernicus =giganteus Bison priscus = bonasus Bos primigenius Elephas primigenius E. antiquus

A subsequent examination of the lion mandible resulted in it being referred to Panthera tigris as the inferior border is straight and not curved as in lion. A femur of a very large feline from Stutton is also thought to be tiger, it is half as long again as the femur of a modern lion which does not ränge as far north nor to so great an elevation as tigers.

The horse must have been common in SufTolk during the Ipswichian interglacial for its bones are common at Brundon and Stoke Hill but not so well represented at Stutton. The large size of some metapodials led Miss N. F. Layard to suppose that the Stoke horses she found belonged to a large race but it is more probable they represent fine stallions.

Rhinoceros bones from Brundon, and Stutton, are scarce and indeterminate but two skulls photographed from the former site are definitely R. hemitaechus. This species presumably lived also in the Gipping Valley but no determinate bones have been found.

The straight tusked elephant Palaeoloxodon antiquus seems to have been fairly common in the Stour Valley but is doubtfully represented in the Gipping-Orwell system. A recent discovery in the Waveney Valley at Wortwell, Norfolk, proves it to be present in hitherto unknown Ipswichian deposits in that region. Other deposits with vertebrate fossils where elephant teeth have been found are at Bures and Long Melford. Presumably similar deposits must occur in the Deben Valley but in the absence of commercial excavations it may be long before they are revealed.

Remains of carnivores are uncommon in any fossiliferous site, particularly at Stutton: in addition to the feline femur an incomplete metapodial of a carnivore was found by S. E. West at the west end of Stutton Cliff which is either Panthera or Ursus, if the latter it is the only evidence of bear from the site.

Avian bones may be more common than the number collected would imply. Only three are known from Stutton and none elsewhere in Suffolk. Owing to the small size of bird remains they are easily overlooked and one, found by the writer, would have been •Excavations at Brundon, Suffolk, 1935-1937.

Soc., 1939-

Proc.

of the

Prehistoric

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washed away by the next high tide, it is part of a humerus of Anas sp (duck), one of the others is the middle portion of the shaft of a humerus of Anser (goose). A bone of turkey found at Stutton was determined at the British Museum (N.H.), and its fossil character was doubted. Mr. Walker has recently informed the wnter that there is now reason to believe turkeys were living here much earlier than was formerly supposed.

Mr. J. N . Carreck of Queen Mary's College, London, has compiled a list of bird remains, in the Natural History Museum, from Ilford and other Ipswichian deposits totalling about a dozen specimens (this includes items in other collections). They include Duck, Goose, Swan, Albatross, Cormorant, and Gull. T h e fossils include feathers and pieces of eggshell. There is nothing to indicate that any fossils listed were the result of systematic mvestigation, or other than that they were chance finds.

Fossil remains of pigs seem to be conspicuous by their rarity, this may be due to their woodland habitat. At Stutt)n, the only Ipswichian site from which Sus scrofa is recorded, only four m complete bones are known. T h e first find was made by Mr. Carreck, the distal end of a metapodial (foot bone) which was undetermined until a skeleton of a Roman pig was discovered in northern Suffolk, the exceptional size of this bone having proved misleading. Subsequently, the shaft of a radius was obtained by F. W. Simpson, and a complete specimen of another, in situ in the upper part of the cliff, noticed by the writer, was unfortunately broken while being extracted from the hard dry clay. Another pig radius from the bed of the Orwell is thought to be post glacial.

Similar Brickearth occurs at King John's Ness, near Pond Hall, Ipswich, extending south toward Bridge Wood. It was exposed in the Ness cliff by the great storm of 30th January, 1953, when an exceptionally lengthy lower molar of a young horse was discovered, the only other bone recorded is an equine tibia from near Bridge Wood. T h i s deposit seems to be limited in area but there are traces of it near Broke Hall, Nacton. F. W. Simpson recorded Brickearth at Stonner Point on the Deben Estuary, but it has not been possible to examine this.* The group of bones of various animals found in a very limited area at Harkstead already referred to formed an interesting problem owing to the way they were mixed up, bison and mammoth intermixed. It seems possible the mammoth feil head first over a cliff onto the remains of two young bison about two years of age, this was indicated by a complete set of teeth of one beast and part of another set, in each set the triple rooted last lower milk tooth was present *Trans. Suffolk Nat. Soc. Vol. 7, p. 77, 1950.

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and this is replaced in the second year. One of these teeth was picked up in 1949 with the uncut first tooth of a foetal mammoth and about three-quarter inch of the rudimentary tusk. Apart from a much decayed elephant femur nothing eise was then visible at the Site. A few years later John Norman with some other lads reported large bones exposed at the site and it was then that an attempt was made to extract them from the sticky clay. Each time a hole was made it immediately filled with water because the site was below the high tide mark and any disturbance of the matrix made the water murky and most of the extraction had to be done by gropinsr in muddy water. Thus the inverted elephant mandible was recovered in fragments and eventually restored. Below this were the bones of one of the fore feet with the lower ends of the metacarpals broken off and no trace of the missing pieces. It was in the process of recovering these bones that most of the bison teeth were obtained. Later the surrounding area was examined and a number of bison limb bones found.

Thanks are also due to John Norman for the collection of the remains of the head of a large pike, Esox lucius, at Stutton. Other teeth of this predatory fish were known and its presence implies an abundance of other species. Remains of fishes are seldom recorded from interglacial deposits but could possibly be found to be more common if someone had patience to wash quantities of suitable clay. The only Suffolk records are from Bobbitshole and Stutton.

Close to the cover of Vegetation along the Orwell shore numerous tracks of rodents may usually be seen and the presence of microtine teeth at Stutton and Stoke Hill suggests similar conditions when the brickearth and loam was being deposited about 100,000 years ago.

Gipping Valley, Barham, Bramford Toward the end of the Ipswichian interglacial the level of the sea was receding as the northern ice fields began to expand. This is shown by the rejuvenation of the Valleys by down cutting of the nvers which resulted in mammaliferous gravels being deposited which are now below the present flood piain formations in valley bottoms. Had there been no commercial exploitation of submerged gravels in the Gipping and Waveney Valleys we might have remained unaware of this. The earliest development was between Hadleigh Road, Ipswich, and the river when teeth of mammoth and woolly rhinoceros were brought up from below the watertable but at the time there was little interest in fossil bones. Later a pit was opened on the south side of Bramford Road from which gravel was pumped from a depth of thirty to forty feet below water level. This resulted in remains of mammoth, woolly rhinoceros, Coelodonta tichorhinus (of which creature a skull once interrupted

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Operations by stopping the pump), reindeer antler fragments, and the remains of a skull, also horse bones occurred together with large numbers of flint artifacts of the Mousterian group of industries. The latter were most probably washed out of earlier deposits by floods which were seemingly frequent and severe to have borne so great a quantity of material downstream. This gravel appears to be the Alling of a former northerly meander of the Gipping extending to half-a-mile from the present river bed and is within a mile of the Hadleigh Road site. It is very evident that much more water flowed along the Gipping Valley at that time.

Reindeer An antler of reindeer, Rangifer tarandus (tundra type), was first discovered when the trench for the sewer was dug in Norwich Road, and from excavations for the Constantine Road Electric Power Station, where the complete dentition of a mammoth was also found and two finely flaked laurel leaf flint blades of the Solutrian industry; another blade was similarly discovered at Bury St. Edmunds.

The commonly found antlers of reindeer are all of the tundra variety now living in Lapland but trenching in Ship Lane, Bramford, resulted in the discovery of an antler of the Canadian woodland type, called caribou. This was unfortunately broken and not all the pieces recovered; the dimensions match those of a fine head in the Ipswich Museum.

Barham Eastall's Pit, Barham, is the most recently opened site and it is due to the co-operation of the owners and stafF that much more has been learned about the late Pleistocene fauna. The site is on a small knoll rising just above the fifty feet contour, it is composed of gravel in which are erratics derived from Gipping glacial outwash, such as garnetiferous schist from Scotland. The lower parts of the workings are, as usual, flooded and this makes it difficult to determine if the deposits belong to more than one period, e.g. one pair of lower elephant molars from above the water more closely resemble Parelephas trogontheri ( P L A T E 10) than M. primigenius of which species a number of teeth have been brought up from lower levels. Similarly the beam of an antler of Cervus elaphus angulatus could only have come from the drier gravel: bones, etc. which have been saturated for centuries most frequently split up on drying out.

Below the gravel, however, there is a bed of silty sand with sparse shells of a species of Succinea and seeds, etc. of aquatic Vegetation, also bones of rhinoceros in a better State of preservation. Bones of rhinoceros, Coelodonta tichorhinus, are more frequent than other animals except mammoth and with the exception of those men-

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tioned, all have a weathered appearance, a number have beeri gnawed by hyaenas. The latter fact alone would be an indication of their having been exposed on a land surface before burial in the gravel.

Hyaena The presence of hyaenas in the Ipswich district was first indicated by a Rhinoceros humerus which had been hollowed by gnawing to get the marrow-filled cancellous tissue. This was obtained by Miss N. F. Layard from an unrecorded Ipswich site.

The Barham bones confirmed this but proof positive of the presence of this scavenging carnivore was produced by Mr. J. R. Aldous, of Haughley, who found the first fossil bone of Hyaena crocuta (Crocuta crocuta). This was a damaged mandible with the carnassial tooth and is the only Suffolk fossil of this genus discovered later than the Crag period. One might infer from the number of rhino bones gnawed that either this pachyderm was easy prey, or that the evidently numerous rhinos suffered a heavy mortality rate.

Bones representing other Barham fauna include urus, Bos primigenius; a small horse, Equus caballus and wolf, Canis lupus.

Waveney Valley Only the relative inaccessibility of northern Suffolk has prevented more frequent Observation of the mammaliferous river gravels. At Homersfield and Weybread it is known that the valley deposits lie on Lowestoft Till from which earlier silts were scoured before aggradation again choked the bottom of the Valley with sand and gravel. At Wortwell trenches for sewers recently exposed ancient lake mud from which teeth and bone fragments of Palaeoloxodon antiquus were obtained for Norwich Castle Museum. This was a hitherto unknown deposit of the mid-Ipswichian interglacial and the better known mammoth-reindeer gravels belong to a later stage of the interglacial or, it has been suggested, to an interstadial of the last glaciation. At Broome Heath, near Bungay, there are river terrace gravels with elephant remains lying on Norwich Crag.

An incomplete, rather battered skull, of an aged Megaceros giganteus from Homersfield had posed a problem because no megacerid remains had been recorded in association with a reindeer fauna but it would appear it was probably derived from an earlier bed by flood water, perhaps zone / of the Bobbitshole pollen sequence, like the organic black clay of the Wortwell site.

The Waveney reindeer antlers are like those of the Gipping and were there more interested collectors who would communicate their discoveries it might prove that this species was much more common than the number of specimens at present known implies.

r

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I I I

There would also be the chance of an increase in the number and variety of animals recorded for the Waveney and other Valley deposits.

I I I

One complete skull of the woolly rhinoceros in Ipswich Museum keeps Company with a less perfect specimen, both from Homersfield.

There is so far no evidence of hyaenas in the area.

There can be little doubt other mammaliferous sites await chance excavation in order to be revealed, also the chance that an intelligent observer is present to report and collect specimens. In such instances it is stressed that bones or teeth of smaller animals are of greater scientific importance than fossils of large animals, which obviously are much more likely to be seen and are generally well known.

There are three sites yielding fossil bones which may be of Ipswichian age, one at Woolpit, long disused, has been reported to have had large bones in the lower part of the brickearth but only one fragment of an elephant limb bone is known. Elephant teeth, etc. together with Levallois flint artifacts in the Bury St. Edmunds Museum are from a former working in the Lark Valley at Sicklesmere. Rhinoceros, mammoth, etc. remains in the old Aldeburgh Museum were without data but there is reason to believe they came from a former pit to the north of Leiston. This inference is based on information of a former local policeman who used to visit the writer at Ipswich Museum and had learned from one of the older inhabitants that bones were found there. The presence of boulder clay exposed in 1954 in a trench near the church, lends support to this conclusion.

The discovery of an antler of reindeer in "Loess" at Icklingham is mentioned in Trans. Suffolk Nat. Soc., 1. 196.

Post Glacial Clacton-on-Sea About a quarter of a Century ago remains were discovered of hut circles of a culture known as Rhinyo-Clactonian because the people are thought to have migrated from the Rhine Valley and settled at Clacton. They made a variety of pottery (Grooved Ware) ornamented with shallow grooves which has also been found at Creeting St. Mary.* The hut circles are now situated below the beach level and represent a vanished land surface beyond the present cliff line.

The cliffs themselves are due to a higher sea level evidence of which exists at the Naze. *In these periods archaeological data have to be considered in place of fossils of earlier ages.

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Walton-on-Naze T h e weathered upper zone of the London Clay with overlying rainwash, slopes down to and dips below the sea where patches of peaty clay represent a former salt marsh, with not less than ten feet of marine clay with shells of Scrobicularia (a mollusc believed to be unable to live except in permanently submerged conditions), above the marsh clay. At present the tidal ränge is about twelve feet and lt has been considered the sea must have been about thirty feet deeper when this clay was deposited. T h e recent salt marsh deposits and the Scrobicularia Clay are now undergoing erosion by the sea.

Orwell Estuary In the Orwell Valley near Pond Hall (Gainsborough Lane), there is a series of beds laid down during periods of fluctuating water Ievels one of which has Mesolithic artifacts, another Neolithic flints. T h e site is marked by the stream f r o m the Crag Springs in Brazier's Wood. T h e Mesolithic flood piain is being rapidly eroded. T h i r t y years ago there was a Stretch of salting from the mouth of the stream to Bridge Wood, about one-and-a-half furlongs in length and fifty feet wide, there was a cart track between the salting and the bank, today the salting has vanished except for a minute patch about six feet long near the wood and the track is now a stony beach. Formerly the shore here, and at other points along the shore, was very soft London Clay. T h e products of recent erosion have covered this with fine sandmaking the soft sticky spots firm to walk on.

Downstream, stretching from the south end of Bridge Wood is a large similar salting which is being rapidly eroded at the southern e n d ; however, upstream is a crescentic sand bar of recent origin extending across the shore from a patch of Phragmites communis, this by arresting floating debris and silt will enable the salting to spread northward.

Felixstowe Fifty years ago the area south of the Pier between the beach and Langer Road was mainly blown sand with sparse M a r r a m grass.

At this point the beach was very narrow and shingle was frequently cast up on the Promenade. Landguard Common is a geologically recent accumulation, Landguard itself was originally an island and the Stour flowed across the marshes along the line of old cliffs which can be seen from the pier to Walton Ferry. Bombs dropped on the common revealed the accumulation of shingle which has diverted the river to the south.

Felixstowe Ferry hamlet stands on a similar accumulation formed by the course of the Deben shifting northward to its present mouth. T h e shingle banks which are diverting the River Deben

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mouth southward are of recent formation. About sixteen hundred years ago a Roman Fort was situated off shore near the Golf House.

The shingle is carried by longshore drift, by-passing Orford Ness and Bawdsey Beach, which thirty years ago was essentially sandy with small dunes between the Manor and the river mouth.

Orford Ness The Alde-Ore river system originally emptied its waters into the sea at Slaughden but perhaps a thousand years back shingle banks diverted the water southward in just the same way as it appears will happen at the Deben mouth. Orford, originally a seaport, was eventually cut off from the sea and Hollesley Bay became silted up.

Traditionally the Stour once flowed to this point!

From these instances it may be seen that geological processes continue and effect changes in the geography of our region.

Pollen analysis of post glacial clays and peats on the continent and our Fen country have shown variations of climatic conditions, alternating wetter or drier periods with consequent changes in the flora, and molluscan fauna. Sphagnum for instance is an indication of increased rainfall during the deposition of peat. There are many places needing investigation to increase knowledge of the more recent prehistoric sites. At Elmsett in a V a l l e y north of the church, at a spot marked "Hole In The Wall", excavation for a pond revealed a prehistoric camp site in the V a l l e y bottom buried below four feet of hillwash from the boulder clay on the plateau.

This implies a very wet period but the site must have been dry at the time when a twenty-five feet spread of ashes accumulated to a depth of three feet over the hearth.

At Dales Road, Ipswich, upwards of ten feet of sandy hillwash has accumulated since Neolithic people lived there over four thousand years back.

A site on the Chantry area of Ipswich had a double hearth site thought to be of Early Iron Age origin which was discovered below about eight feet of sand which was deposited during the past two thousand years.

At the beginning of the Mesolithic period pine was the principal tree but it decreased and birch became slightly more common, pine increased but was replaced by hazel with some elm, lime and oak.

This was followed by the dominance of mixed oak forest. In the Bronze Age beech was the principal tree but by the Roman period it was a mixed oak group associated with hazel, pine and spruce.

These changes in the flora are entirely due to alterations in climatic conditions which alternately favour northern or southern species.

PLATE 9

Displacement of L o n d o n Clav bedding in Harkstead C l i f f (1951) by a hemispherical mass of Stutton Brickearth. T h i s and other similar features are due to pressure at right angles to the face of the cliff.

[Photo

by Hallam

Ashley

PLATE

10

P a i r o f t h i r d l o w e r m o l a r s m o r e c l o s e l v r e s e m b l i n g Parelephas trogontheri than M a m m o t h .

F r o m t h e late P l e i s t o c e n e Valley g r a v e l s o f t h e R i v e r G i p p i n g .

T h e y are i n a b e t t e r State o f p r e s e r v a t i o n t h a n M a m m o t h t e e t h also f r o m t h e B a r h a m site. " [ P h o t o by F. W. Simpson

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The present assemblage of trees, shrubs, etc. in Britain is not truly representative of our climate because of the introduction of exotic species. Lesser members of the vegetable world such as Claytonia perfoliata, Galinsoga parviflora, and Canadian fleabane have become established in Ipswich, the seeds having been windborne as ships from the western world were being discharged at the dock; doubtless they have become more widespread.

Considerable assistance has been received over many years from workers in many fossiliferous pits who have preserved many interesting fossils, and from owners of sites who have allowed frequent visits and the collections of specimens. In each instance the identity of the animals represented by the fossils has been explained. In the beginning much help and encouragement was given by Dr. A. Tindell Hopwood and Miss Dorothea Bäte, of the British Museum. To the keen interest of John Norman from his school days and to all who have directly and indirectly helped in many ways, my grateful thanks are given. Not least of all who have given encouragement was the late Guy Maynard, with whom I was associated at Ipswich Museum for over thirty years, to him especial thanks are due, also B. W. Sparks and R. G. West, to whom sincere thanks are due for over ten years of co-operation.

H. E. P. Spencer, F.G.S., 43 Benacre Road, Ipswich.