Crag Mammalia

153.

THE CRAG MAMMALIA

By H . E . P . SPENCER, F . G . S .

THE important collection of Crag mammalian fossils in the Ipswich Museum, in which the Norwich Crag fauna is poorly represented, has been enriched by the welcome addition of a small number of bones and teeth from Easton Bavente and Covehithe Cliffs, collected by Messrs. D. and P. Long of Lowestoft Any specimens from this locality are valuable for study but some of the new fossils are of more than ordinary interest as they are additions to the fauna list from this deposit. 1 he new fossils include a lower left third pre-molar of an extmct species of eiant deer, Megaceros verticornis ; a well preserved nght lower molar of zebra Hippotigris suessenbornensis ; the distal end ot a metacarpal and an os pedis of either horse or zebra, also some foot bones of elephant, possibly E. mendionahs. There is a smal number of teeth of vole, but these will be described by the Earl of Cranbrook (p. 155).

The discovery of a tooth of M. verticornis in the Norwich Crag forms a link between finds in the Red Crag and the Cromer Forest Bed fossils. The basal portion of a cast left antler, collected bv her father at Trimley St. Mary, has been presented to the Museum by Miss J. C. N. Willis. Fossils of the giant deer are verv rare in the Crag but are common m the Cromer Forest Bed. The condition of the specimens indicates the animals were living at the time the crag sands were deposited. Megaceros giganteus, the so-called Irish Deer, is the best known member of the genus, it survived in various parts of Europe until the end of the Ice Age. It is not generally understood that the mammalian remains found in the Crag are of two classes, firstly those s p e c i m e n s which were already fossils before Crag times and are derived from older strata, secondly those of animals which were living at the time the Crag was being deposited. Bones, etc., of the hrst type are always very heavily mineralised, varying in colour from lieht brown to nearly black and usually very glossy. Among these are Hyracotherium, a remote ancestor of the horse family from Eocene beds ; Hipparion gracile, the Miocene three-toed horse • three species of mastodon, borsoni, longirostris and arvernensis; tapir various pigs ; an Axis Deer, A. pardtnensis and Cervus suttonensis. The latter seems to haye been much rarer than the Axis All the remains of the land mammals are mixed with abundant bones and teeth of whales and sharks and other manne animals. The bones of the contemporary animals are pale coloured when found in the Red Crag but in the Norwich Crag they are usually dark brown and not so highly pohshed as the older fossils ; they are not so heavily mineralised.

154

T H E CRAG MAMMALIA

It is believed that there has been no attempt to compile a list of contemporary Red Crag mammals, largely perhaps because the two classes have not been recognised. So far as the Ipswich Museum collection is concerned the list is as follows :— genus and species undeter mined. „ Ursus Parvensis.

Bear „ Cervus (Euctenoceros) Deer falconeri. „ Cervus perrieri.

Deer „ Castor Pveterior.

Beaver Trimley St. Mary Megaceros verticornis.

Giant Deer undetermined, Psperm whale. ,, Sutton Whale Equus robustus. „ Waldringfield Horse Elephas antiquus. „ Falkenham Elephant M. arvernensis.

Mastodon locality unknown

Whale

from Bramford

from the Norvvich Crag :— Whale no locality Mastodon „ „ Elephant from Easton Bavents Giant Deer „ Deer ,, „ Deer „ Sizewell Zebra „ Easton Bavents Vole „ » Vole „ Covehithe

Balaenoptera sp.

M. arvernensis.

E. Pmeridionalis.

Megaceros verticornis.

Euctenoceros sedgwicki. indeterminate.

Hippotigris suessenbornensis.

Mimomys pliocaenus.

M . intermedius.

Since, so far as is known, there are no active workers at present interested in Pleistocene mammalia, more particularly with regard to the Crag fauna, it is very desirable that any bones of this period which may be in private collections in the county, or elsewhere, should be examined and recorded at the museum.

The condition of the known sections is such that without great expense very little material is likely to be discovered in the future.

Since the above was written there has been a new discovery of mammalian bones contemporary with the Red Crag at Felixstowe. T h e find was made in a sewer trench 600 yards East of Grange Road, opposite the end of Ferry Lane, below ten feet of comminuted Red Crag. There are two specimens, both those of an immature deer, possibly of either the genus Megaceros or of Euctenoceros.

One specimen consists of part of the left side of the skull with pedicle and a portion of the base of the antler. It is most unfortunate that this fossil has been much damaged by the workman's shovel, the front part of the antler base has been split off so that the junction of the brow tine, an important feature

T H E CRAG

MAMMALIA

155

for determination, is not present; also part of the inner side of the pedicle has been similarly lost. The front of the pedicle appears to have sloped in line with the facial bones and not to have been projecting, at an angle, as is usual, thus curving into the skull line ; there is a deep crescentic groove at the back.

The antler is at a slight angle with the pedicle and the burr is very slight.

The other bone is a calcaneum (Heel bone), which, in view of the great rarity of contemporary deer remains in the crag, and from its having been found close to the other specimen, may almost certainly have belonged to the same animal.

These important fossils and the circumstances of their discovery were reported to the Museum by a member of the Surveyor's Department at Felixstowe.

FOSSIL VOLES THE Ipswich Museum has received from Mr. R. A. Long some interesting vole teeth from Easton Bavents and Covehithe. The Easton Bavents remains consist of two first lower molars, a first and a second upper molar, two upper incisors and one lower, with some fragments. The lower molars have each two roots and the small enamel islet on the anterior loop on the crown which is characteristic of the enamel pattern of that tooth in Mimomys pliocaenicus Forsyth Major, in adult stages of wear. The first upper molar has three roots and is also attributable to M. pliocaenicus. The second upper molar has only two roots though the base is damaged and it might have had a third : all that can be said of it is that it is of some species of Mimomys. The Covehithe specimen is a single first lower molar attached to a portion of the lower jaw : the tooth certainly has roots but they cannot clearly be seen. The anterior loop of this tooth shows no signs of the complexity which is typical of M. pliocaenicus, M. savinii Hinton, and M. majori Hin ton, and while it is impossible to dogmatise about a single tooth, it would appear that it should be attributed to M. intermedius, Newton. M. pliocaenicus has alreadv been found in Suffolk (Trans. II, pt. 1, p. 19, 1932) but no remains of M. intermedius have hitherto been recorded from the county though it has frequently been found in Norfolk.

M. pliocaenicus is the earlier of the two species : it has been found in the Norwich Crag in Norfolk and Suffolk (in association with