from the Red Crag. 355 



Castor veterior, n. sp. 



Two molar teeth, one of which is represented in PI. VIII. fig, 5, 

 and an incisor of the lower jaw, in fig. 6, belong to Mr. Whin- 

 copp's collection. They were obtained from a Red-Crag pit in 

 the neighbourhood of Sutton, and are in the usual mineralized 

 condition of Red-Crag Mammalian remains, being very heavy 

 and presenting an iron-stained glossy surface ; so that any per- 

 son with a moderate experience in these matters would at once 

 recognize their origin. They unmistakeably belong to a species 

 of Beaver. The molar figured I have carefully compared, with 

 the assistance of Mr. Davies, with the skulls of Castor Europteui 

 from the Lincolnshire fens, in the British Museum, as also with 

 teeth from Grays, and a specimen in my own collection of the 

 Canadian Beaver. I find that it is the premolar of the upper jaw 

 of the left side, the dental formula of the Beaver, as given by 



Prof. Owen, being t. |, pm. ~^t in. j;::^ = 20. It differs chiefly 



from the specimens I have examined in the great length of the 

 fang, and also in the arrangement of the folds of enamel on the 

 crown or flat grinding-surface. This resembles that of the 

 Castor Canadensis rather than that of the C. Europeeus, but 

 differs from it in the greater width of the fossse of dentine be- 

 tween the enamel ridges, and in the greater inward development 

 of the large anterior fold or lobe. In C. Europaus the pre- 

 molar of the upper jaw presents the same general arrangement 

 of the enamel ridges ; but certain minor variations may be de- 

 tected which do not exist in the Crag or Canadian species. 

 These relate merely to the proportion and development of cer- 

 tain folds, and are probably of little value as specific characters. 

 I do not, however, hesitate to consider the Beaver to which the 

 teeth under description belonged as a distinct species. Fossil 

 Beavers have been met with at Perrier and in the Val d'Arno/ 

 the latter being a Miocene, the former a Pliocene deposit. The 

 Crag form does not resemble either of these, and I therefore 

 distinguish it as Castor veterior. The C. Europteus has been 

 met with in a fossil condition at Grays in Essex, and at Ilford, 

 associated with the remains of Elephas antiquus, Rhinoceros 

 tichorhinus, &c. The Trogontherium Cuvieri has a tooth very 

 differently marked from that figured, the age of which would 

 otherwise have induced one to compare the two. 



There is little doubt that the Beaver, like all the terrestrial 

 Mammalia found in the Crag which are known (with perhaps 

 one or two exceptions), was derived from a previous Miocene 

 deposit. 



I should mention that the incisor tooth, which is imperfect, 

 presents no very striking characters, but is of a very rich black 



23* 



