William Davies — Pleistocene Mammalia. 99 



covered in the Fens of Lincolnshire and described by Prof. Owen 

 in his " British Fossil Mammals." Its fossil remains are also said 

 to be found in France ; and in the Crag, enormous incisors of 

 probably a closely allied animal {Trichechodon, Lank.) are far from 

 nncommon. Like the Lemming and other land animals, the Walrus 

 may have migrated from our shores when the climate and waters 

 were no longer congenial to its existence. 



The skull of the Beaver, though undoubtedly fossil, may have 

 been a later introduction; and the bones of the larger Cetacea I 

 regard as semi-fossil bones of Post-Tertiary age. 



It is Mr. Owles' impression that any large collection of similar 

 fossils will never be made again from the area in which his collec- 

 tion was obtained. The Dogger Bank for many years, he states, 

 has been so scraped and sifted by the fishermen's dredge, that a ' 

 tooth or a bone is now seldom brought to the surface on it. 



From Preglacial deposits there are a few teeth of Elephas 

 antiquiis and Elephas meridionalis, of this species there is a fine 

 entire germ of an ultimate lower molar. 



In the collection, and obtained from the same sea area, I dis- 

 covered the centrum of an anterior caudal vertebra of an Iguanodon, 

 which must have come from a much older deposit. Externally it is 

 indistinguishable from the other bones, having the same deep brown 

 colour, and its surface is covered with the shells of small Balani, 

 tubes of Ser-pulce, and cells of Polyzoa, but its mineral condition is 

 very dilferent, petrefaction being complete, all its cellular tissue 

 being permeated by foliated sulphate of lime, resembling in this 

 respect many Dinosaurian bones from the Wealden of the Isle of 

 Wight ; and thus giving it a Wealden rather than a Lower Green- 

 sand facies. But whatever the deposit from which it was obtained, 

 it has not been transported from a distance, for it has been subject 

 to no water-wearing action ; the epyphysial rugosities at either end 

 are very slightly worn, and the natural margins are intact, as is 

 also the chevron bone depression ; the walls of the neural arch are 

 present, but the top with the process is absent. The fractured 

 surfaces of the neural walls show the splintery fracture of a recent 

 bone, with the points very slightly abraded, as if the spine had been 

 broken off before fossilization had commenced. This interesting 

 fragment is a geological puzzle ; that it was originally deposited 

 where it was discovered is proved by its angularity, and there is no 

 doubt as to its species, which is also limited to the Wealden and the 

 Lower G-reensand. Its mineralization points to the former as the 

 bed from which it was probably derived, yet there is no present 

 evidence that the formation extends to the Norfolk coast. The 

 officers of the Geological Survey employed upon that district may 

 possibly solve the difficulty. 



Of the Norfolk coast fossils, the British Museum acquired in 



1842 and 1843 the collections made by the Kev. C. Green from the 



Forest-bed in the neighbourhood of Bacton, Ostend, etc., and briefly 



described by him; ^ and subsequently, in 1858, the large and well- 



1 The History, Antiquities and Geology of Bacton (Norwich, 1842). 



