The Crag Elephant (Archidiskondon Meridionalis)

THE CRAG ELEPHANT (ARCHIDISKODON

MERIDIONALIS)

HAROLD E . P . SPENCER,

F.G.S.

FROM time to time over the past Century and a quarter,re mains of elephants have been found in the Red and Norwich Crag Sands, these mainly consisted of portions of teeth. At Falkenham, near Felixstowe, a pair of lower molars was discovered, one of these teeth was broken and a few plates from the middle are missing.

They are preserved in the Ipswich Museum. It was the opinion of Sir E. Ray Lankester that they could not have come from the Red Crag but from more recent sands above the Crag. At the site of this discovery there are no later deposits above the Crag but he may have been misled by the upper part of the formation having been decalcified.

Elephant teeth in Red Crag found during the Coprolite diggings seem to be extremely rare and accordingly portions of teeth were cut into sections which became distributed in various museums, i.e., the British Museum (Natural History), London; Leeds; York; Birmingham and Manchester.

In the monograph on the British Fossil Elephants, A. Leith Adams (1881) figures two portions of teeth (then at Leeds) pl.

XXVI, figs. 2 and 4 as Elephas antiquus but the thickness of the enamel is greater than is normally found in this species. The fact is that by a study of the much greater number of teeth now available there is no evidence that this species existed during the Crag marine epoch.

Until the commercial exploitation of the Westleton marine shingle for making concrete, the main source of mammalian bones of the Norwich Crag fauna was the cliffs at Easton Bavents near Southwold, whence elephant teeth, limb bones, calcanea, part of a mandible, etc., have been obtained as a result of marine erosion.

Similar fossils have been dredged from the sea bed off Southwold and are cast ashore at Walberswick during storms.

At Holton, near Haiesworth, the first fossils recorded were tines of antlers of the large early Pleistocene deer Euctenoceros sedgwicki and cetacean vertebrae. As the section was worked back into the north Valley slope bones of a variety of animals were discovered but the greater number of specimens were of elephants representing animals of all ages. This is a feature common to the mammaliferous deposits of later interglacials which show a heavy mortality amongst young elephants. In a recent broadcast by Peter Scott it was stated that many young elephants are killed by tigers in Asia but there is as yet no evidence of tigers in Suffolk at this early period; there are teeth of leopards recorded from both

128

Transactions of the Sujfolk Naturalists',

Vol. 14, Part 2

Red and Norwich Crags which have a similar mammalian fauna to the Westleton Beds. Tiger has been proved to have lived in the Stour Valley at Brundon during the last interglacial and probably also at Stutton.

The remains of elephants occur at all levels to which the pebble beds have been worked at Holton, except perhaps the uppermost.

They were notably frequent below the water table at the eastern end of the pit where gravel was first pumped up from about thirty feet below water level and later dredged up by grab. At the lowest level the bones and teeth occurred in a Stratum impregnated with Marcasite (iron sulphide). At this level there was a quantity of fossil wood and a number of fragile shells amongst the pebbles, chiefly bivalves.

Since 1953, the small pit at Reydon, Southwold, has been worked by the St. Ives Sand and Gravel Co., and has now reached proportions rivalling Holton. Here the upper beds have more molluscan remains than Holton where shells are represented only by hollow moulds from which they have been dissolved by percolating water. So far as is known the upper part of the section is not mammaliferous but elephant remains have been brought up by dragline from an unknown depth below the water table.

A few years ago the drag cut through a large tusk, or perhaps pair of tusks, which broke into fragments and were scattered over the heap on which the gravel was tipped. A number of the fragments were collected and these proved surprising in that the condition of the ivory was quite unlike what was to be expected compared with fragments of ivory from Holton. Generally fossil bones from Crag beds are more or less stained by iron or sometimes encrusted with limonite, the Reydon tusk was however largely unstained and only the outer layers indurated and faintly discoloured, the interior was found to be soft and chalky. Elephant tusks, like trees, have an annular structure as a result of which fossil tusks all too frequently break readily into fragments, particularly when they are buried in pervious sandy or gravelly deposits.

Tusks buried in clay are generally better preserved.

It cannot be said if the tusk, or tusks, were with, or had been detached from the skull but a very fine third molar of an adult bull was discovered about the same time, this is now in the new display of early Pleistocene mammals in the fossil mammal gallery of the British Museum (Natural History). T h e fossil condition of this tooth is in much the State to be expected of a tooth associated with the tusk in question. About two thirds of a smaller tooth in a more mineralised State is now in the Institute of Geological Sciences, South Kensignton.

THE CRAG ELEPHANT

129

When visiting the Reydon Pit early in November (1967), Mr. A. Teager, one of the pit staff, produced two small pieces of rib which were obviously from an elephant skeleton. Like the tusk described above they were only partially mineralised and unlike most fossil bones bore no traces of battering by the pebbles in which they had been buried. It was stated that a number of rib fragments had been collected, some were lengths two feet or more long, also there were some larger bones which may, or may not have been part of the elephant skeleton.

In this country elephant skeletons, even only partly complete, are very rare and the possible discovery of one some two million years old would be something most exceptional It was learned however that a week or so previously a man visited the pit and mentioned the name "Spencer" and was accordingly allowed to take the bones. Under these circumstances it is not possible to determine if all the bones actually do belong to one skeleton and if they are in some private collection unrecorded they are as good as lost to science. All that could be ascertained about the man is, that he had a beard.

On a subsequent visit, the excavator having continued working in the same part of the pit, it was found that on the morning of the visit a large bone had been brought up, this was found to be a humerus, broken in two with the proximal termination missing.

The small size indicates the bone is from a female and Professor Azzaroli, who is very familiar with this Villafranchian species of elephant, confirmed the slender proportions of the bone were indicative of A. meridionalis*. In the absence of the other bones there is nothing to show if this humerus belonged to the skeleton but its well preserved character suggests it might be.

If any reader can give any information regarding the ribs and other bones which will enable an examination to be made for the record it will be greatly appreciated.

The great frequency of elephant remains in the Norwich Crag and Westleton Beds is mainly due to the fact that the larger limb bones (a femur of a large bull may be five feet long) can be broken into a number of small pieces, which is actually what has happened.

Except for rare carpal and tarsal bones, even partly complete long bones of any animal are very uncommon. Of elephant only two incomplete bones are recorded, a humerus each from Holton and Reydon. Perhaps the rarity of bones of smaller beasts is due to the fact that they are less noticeable in a lorry load of gravel. *This was the last day of a three week visit to England by the Professor.