Prehistoric Mammalia of Suffolk

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MUD FAUNA OF THE STOUR ESTUARY

237

The following species occurred at the localities shown :— Oligochaeta II. Mya arenaria IV, V, VI. Polydora sp., IV. Linens gesserensis V, IX. Amphiporus lacteus V, VI. Gattyana sp., VI. Ampharete grubei VI, V I I IX. Audouinea tentaculata VI, V I I , IX, X. Sphaeroma sp.. VI, IX. Amphitrite johnstom VI. Sagartia elegans VI. Melita palmata ~VIII. Scolecolepis fuliginosa X. Key to LocaVties :— i—Buck's Horns. II—Cattawade Bridge. III—Manningtree Garage. IV—Manningtree. v—Mill House.

vi—Stutton Ness. VII—Wrabness. VIII—St. Clements. ix—Erwarton Ness. x—Shotley.

REFERENCES.

1. Alexander, W. B., Southgate, B.A and Bassindale, R. T h e Salinity of the water retained in the muddy foreshore of an estuary. Journ. Mar. Biol. Assoc. 18, p. 297, 1932. 2. Milne, A. T h e ecology of the T a m a r estuary 3. Salinity and temperature conditions in the lower estuary. Journ. Mar. Biol. Assoc. 22, p. 529, 1938. 3. Smith, R. I. T h e ecology of the T a m a r estuary 7. Observations on the interstitial salinity of intertidal muds in the estuarine habitat of Nereis diversicolor. Journ. Mar. Biol. Assoc. 35, p. 81, 1958. 4. Spootier, G. M. and Moore, H. B. T h e ecology of the T a m a r estuary 4. An account of the macrofauna of intertidal muds. Journ. Mar. Biol. Assoc. 24, p. 283, 1940.

THE PREHISTORIC MAMMALIA OF SUFFOLK by

HAROLD E .

P.

SPENCER,

F.G.S.

THE recent discovery of a portion of a humerus of the so called " Cave Lion " has led to the realisation of the great rarity of the fossil remains of carnivores in this part of the country. For more than half a Century extensive additions have been made to the large collection of Pleistocene mammalian remains in the Ipswich Museum, and during the latter half of this period a number of sites have been kept under Observation by members of the staff with negligible results as far as fossils of beasts of prey are concerned. Detailed records of fossils found in the Crag are seldom preserved as the workmen were, understandably, mainly interested in getting a good price for them, while collectors were chiefly concerned with adding rare specimens to their cabinets. It is fortunate mammalian fossils from the Crags are easy to recognise, although we may never know from what level in the Crag they were obtained.


238

PREHISTORIC MAMMALIA

The records from the Crags, which incidentally are earliest Pleistocene, are taken from the Survey Memoir by E. T . Newton. " The Pliocene Vertebrata of Britain ", 1891. All the specimens preserved at the British Museum (Natural History), the Geological Survey Museum, the Sedgwick Museum, Cambridge, and the Ipswich Museum, have been checked, but those said to be in York Museum do not appear to have been seen by anyone for many years. It will be seen from the following list how little material is preserved and this reflects the rarity of Carnivora compared with fossils of grazing and browsing animals. Felis pardoides, Owen. A left lower sectorial tooth (Ml), now in the Ipswich Museum Crag Collection, was discovered in the Red CragatNewbourneandis indistinguishable from the corresponding tooth of the existing leopard, (Felis pardus). Another tooth, a pre-molar (pM4), is also in the Museum ; whether this is the tooth which is said to have been found in a pitfivemilesfromNewbourne is uncertain. Recently half of another pM4 was found in the Norwich Crag at Easton Bavents by Lord Cranbrook ; it is now in the British Museum. Three, possibly four, isolated teeth constitute the only evidence of Pards, or Leopards, in these islands at least a million years ago, but there is no later evidence of this cat. Hyaena striata, Zimmerman. Hyaena crocuta, Erxleben. Both the Striped and Spotted Hyaenas are represented by teeth in the Red Crag or Forest Bed, (both deposits are included in the First Inter-glacial). T h e former now lives in India, S.W. Asia and in Northern Africa, and although its fossil remains have been recorded from French caves it is, except for these teeth, unknown here. Spotted Hyaenas have left much more evidence of their continued occupation of this country from Cromer Forest Bed times throughout the later Pleistocene epoch to the close of the " Ice Age ". In Suffolk the evidence is scanty, consisting mainly of tooth marks on bones from sundry sites which is confirmed by the discovery of an incomplete mandible from river gravels at Barham. The earliest fossils of H. crocuta, other than Crag, are from the Forest Bed of Corton and Kessingland. It is at present confined to Africa south of the Sahara. Canis lupus, Linnaeus. Canis vulpes, Linnaeus. Both the Wolf and Fox are known from fossils in the Red Crag and their remains occur widely throughout the Pleistocene to modern times. The former has been largely exterminated by man except in North America and Northern Asia. Fossils are rare and Fox is even more scarce and apart from a remarkably well preserved palate from the Red Crag at Boyton (now in the British Museum), only a few bones from Stoke are known. T h e apparent rarity of small mammalian fossils may be due to their being overlooked.


PREHISTORIC MAMMALIA

239

Ursus spelaeus, Rosenm체ller. T h e " Cave Bear " is not known from any Crag deposits but remains are known from the Forest Bed and later deposits and while common in caves appear to be rare in river gravels. This bear lived in the Stour and Gipping Valleys but remains are recorded from Brundon and Stoke only. Ursus arctos, Remains of this bear occur in neighbouring counties but so far there are no records from Suffolk sites. Panthern leo var. spelaeus, Goldfuss. T h e " Cave Lion " like the " Cave Bear " is best known from cave deposits and its popul채r name, while convenient, perhaps tends to create the view they were mainly cave animals. When doubt was expressed to Professor Zeuner regarding the validity of the name, he stated the term is used for fossils of true lion and another carnivor intermediate between lion and tiger. T h e present climatic r채nge of modern tigers suggests some of the fossil bones are the remains of true tigers ; they r채nge to the 55th parallel of north latitude in eastern Asia while the lion has not been proved to have gone north of the 45th parallel. It is probable this predator may have been far more abundant in the open grassy and park-like country than the number of fossils indicates. Conditions for the preservation of bones are not good in such country, and it is only where skeletal remains are quickly protected from Hyaenas and natural decay that they are likely to become fossil. Five sites in Suffolk with remains of lion have been recorded. The earliest was found during the construction of the railway at Worlington, near Mildenhall, where the fossils are associated with hippopotamus. If lion fossils were discovered during the construction of the railway at Ipswich during the 1840's there is no record ; however, most of the bones of a hind foot (and others) were recovered by Miss N. F. Layard in 1919. A mandible found in 1939 at Brundon is undoubtedly that of a tiger. About 1945 an incomplete metapodial and a large femur were found in the Brickearth at Stutton ; the latter is half as long again as a comparable bone of modern African lion. T h e latest discovery (mentioned above), of a distal end of a humerus at Barham in the submerged river gravels is also of large size and dates back to the close of the Pleistocene. T h e other remains are all last inter-glacial and may be as old as a hundred thousand years. T h e Barham specimen was associated with remains of elephant, rhinoceros, horse, reindeer, hyaena and wolf, also flint artifacts made by man. The skeletal remains are all too frequently fragmentary and owing to the very close relationship of the larger members of the cat family, which permits interbreeding, it is usually impossible to distinguish specific differences except in skulls and mandibles, which are even more rare. It is chiefly by external characteristics the species are determined.


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PREHISTORIC MAMMALIA

Machaerodus sp. Sabre toothed Tiger. Fossils of this extinct family are extremely rare in this country so it cannot be expected many would be found in East Anglia. Teeth referable to Machaerodus are recorded from Red Crag. An incomplete canine tooth is in the Ipswich Museum from the Norwich Crag at Covehithe. This was originally referred to Homotherium because it appeared to lack the serrations on the posterior edge which exhibits marked signs of wear. Close examination, however, reveals a row of minute dark marks which correspond to the spaces between the serrations of the anterior edge. These undoubtedly indicate the former presence of serrations on both edges as may be seen on the perfectly preserved tooth from the Cromer Forest Bed now in the British Museum. Machaerodus has serrations on both edges of the canines, Homotherium has them on the anterior edge only and a third genus has none at all. This family had its origins back in the Eocene epoch (F. E. Beddard, " M A M M A L I A ", Cambridge Natural History, 1 9 0 2 , p. 4 0 2 ) and O . Schmit, " M A M M A L I A ", International Science series, 1894, p. 276), thought it became extinct during the Miocene epoch which lasted about 20 million years. Lydekker " Catalogue of British Fossil Mammals " 1894, lists remains of unknown date (possibly derived), from Kent's Cavern, Torquay. T h e latter may be of more recent date than the Forest Bed, but the evidence indicates the survival of at least one genus into the Pleistocene (first-interglacial of about half a million years ago).

ELMINIUS MODESTUS (Darwin) from the Stour Estuary by

J.

COLLINS

the collection of fossil material from the Inter-glacial deposits on the North bank of the River Stour at Stutton on 9th July, 1959, large numbers of the recent barnacle Elminius modestus (Darwin) were observed on pebbles exposed at low tide. A search was made to see if any specimens could be found attached to other objects and one dead Shore-crab, (Carcinides maenas L.,) was found with four individuals on its carapace. Also on the carapace were three specimens of Baianus improvisus (Darwin). T h e basal length of the largest specimen ofE. modestus was 6.5 mm. while the largest specimen of B. improvisus, which was seen to be overlapping an individual of E. modestus, was 5.4 mm. DĂœRING


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