f 1 » On the Fossil Bones 



things. Did the horses to which they belong rciemble 

 those of the present day in every respect ? 



I must confess that comparative anatomy cannot answer 

 this question. 



T have carefully compared the skeletons of several va- 

 rieties of the genus Equus, those of the mule, the ass, th6 

 zebra, and the couagga, without being able to find in them 

 a character sufficiently fixed to entitle me to hazard a de- 

 cision. If we could obtain an entire fossil head, we might 

 perhaps set on foot some comparison ; but with the other 

 bones, most of which are mutilated, we can obtain no result. 



We may therefore rest assured, that one species of the 

 horse genus served as a constant companion to the elephants 

 or mammoths, and to the other animals of the same aera, 

 the bones of which fill our large basins; but it is impossible 

 to say in what respects they resembled any of the species 

 koown at present. 



It only now remains to point out the characters by which 

 we may distinguish the bones of horses. As it is with the 

 ox and the buffalo that they are most liable to be con- 

 founded, it is with these that we must compare them. 



The upper grinders of horses are prismatic, like those of 

 the ox and buffalo, and marked in the same way with four 

 crescents ; but they have besides a fifth, in the midst of the 

 inner edge. The lower grinders are more compressed, and 

 have four crescents in the horse as well as in the ox ; but 

 instead of being parallel in pairs, they are alternate, the 

 first of the inner edge corresponding to the interval of the 

 two of the outer edge. 



The shoulder-blade of the horse has its spine more ele- 

 vated at the upper third part of it, and decreases from 

 thence to the acromion. In the ruminating animals there 

 is also an elevation at the same spot ; but it is at the lower 

 extremity, and at the acromion, that the spine is most pro- 

 niinent. 



In the humerus of the ox, the great tuberosity rises far 

 above the rest of the upper head, and there is only a groove? 

 for the biceps humeri ; in the horse this tuberosity does not 

 rise more than the rest, and there are two different grooves 

 in. front. 



The camt-I and other ruminants resemble the horse more 

 than the ox in this respect. 



The cubitus of the ox, although attached to the radius, 

 may be distinguished throughout its whole length ; that of 

 the horse is entirely lost from its superior third part, being 

 •nlv marked afterwards by a kind of thread. 



The 



