PALAEONTOLOGY 



THE river gravels and alluvial deposits, the London Clay and 

 the Cretaceous rocks of Kent are noted for the abundance and 

 fine preservation of their vertebrate fossils ; and a large number 

 of genera and species have been described from the two last- 

 named formations on the evidence of Kentish specimens. The London 

 Clay of Sheppey has in fact furnished practically all our information 

 with regard to the birds which inhabited England during the early 

 part of the Eocene period ; and the vertebrates of the Folkestone Gault 

 are to a great extent unknown elsewhere. The fissure of Pleistocene 

 age at Ightham has revealed the existence at a time when the mammoth 

 and woolly rhinoceros roamed over the south-east of England of a fauna 

 largely composed of species still existing. Of the other Pleistocene 

 deposits in the county perhaps the most important are the gravels at 

 Aylesford and Maidstone and the so-called bone-bed at Folkestone.^ An 

 interesting fact in connection with the county is the discovery of fossil 

 remains of the woolly rhinoceros at Chartham about the middle of the 

 seventeenth century, to which further allusion is made below. 



The vertebrate fauna from one of the fissures in the Kentish Rag 

 near Ightham, which, as already said, is considered to be of Pleistocene 

 age, has been described by Mr. E. T. Newton,^ and is remarkable for 

 the number of species of the smaller mammals, whose remains are so 

 seldom preserved in formations of this age. The remains include those 

 of several kinds of bats, all apparently referable to existing species ; as 

 well as of the common and the lesser shrew and the mole. The 

 Ightham Carnivora comprise the wolf, fox, Arctic fox {Canis lagopus), 

 wild cat, cave-hy^na {Hycena crocuta spelaa), brown bear, badger, otter, 

 weasel, polecat, and a species regarded as an extinct kind of polecat and 

 named Mustek robusta. The rodents include an extinct species of suslik 

 [Spermophilus erythrogenoides) ; the wood-mouse [Mus sylvaticus), and an 

 extinct species of the same genus named M. lewisi ; six or seven species 

 of voles, some of which are unknown in the living state in Britain ; 

 the Norwegian lemming {Lemmas lemmas) and the banded lemming 

 [Dicrostonyx torqaatus) ; the common pica {Ochotona pusilla) ; the 

 common hare, the mountain hare {Lepus timidas), and the rabbit, the 

 remains of the latter being probably of later age than those of the other 

 mammals. 



» See S. J. Mackie, Quart. Journ. Geo!. Soc. (185 i) vii. 257. 

 8 Ibid. (1894) 1. 188, and (1899) Iv. 419. 



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