FOSSIL MAMMALIA. 91 



These characters, whatever the age of the animal to whom 

 this jaw belonged might have been, or whatever the complete 

 number of teeth might have been in the animal's full deve- 

 lopement, clearly indicate a distinct genus, and also prove that 

 its regimen was more exclusively graminivorous than that of 

 the rhinoceros, and more resembled that of the horse and 

 elephant. It is also extremely probable that it bore, in other 

 respects, very strong relations to the rhinoceros and to the 

 horse, and formed, perhaps, an intermediate link between 

 these two genera. It appears to have been about the size of 

 the former. 



The enamel of the teeth is of a beautiful white and very 

 hard. It strikes fire with steel. The osseous substance is 

 yellow at the coronal, brown below. It effervesces with acids. 



It is not known in what part of Siberia this precious relic 

 of a former world was discovered. 



HOESES. 



On the fossil horses it would be useless to dilate. Their 

 remains occur in a vast variety of places in the same strata 

 with the bones we have been reviewing. This proves that 

 they were contemporaneous with those extinct pachydermata ; 

 but nothing has as yet been observed respecting them, to 

 indicate a distinct species from the existing. The Baron 

 merely remarks that the bones are not as large as the bones of 

 our large horses, but more approaching the size of those of 

 the zebra, &c. 



No well- authenticated remains of the genus of the swine 

 have been found, except in the peat and other very recent 

 strata, and of course not different from our present races. 



The Gigantic Tapirs. 



These are the first of a series of fossil animals which exhi- 

 bited a strong affinity with the existing tapir in the transverse 

 hillocks of a part of the molar teeth, and also in their general 



