62 ANTILOCAPRin.T.. 



genera of Bovidcv and Cervida-, more especially as the placenta 

 of very few species of the large group of Antelopes and Deer is 

 known. 



Dr. Sclater proposes to divide the Ruminantia unc/idigrada with 

 placenta ])ol}'cotyledonaria,intope(7fs didactifli andpedes tetrad act ijli; 

 but this character will not separate Antihcaprklcp from Bovidce, un- 

 less he proposes to arrange several animals which have been called 

 Antelopes, and which have simple horns with a permanent horny 

 sheath, and which therefore do not agree vrith his other characters 

 of the group, in the family Antilocaprida ; for the genera Nesotragus 

 and Nanotragus, and one species of the genus Calotragus, are as de- 

 stitute of false hoofs as the genus Ant'docapra. Dr. Sundevall con- 

 siders the absence of this false hoof of so little importance that he 

 places two species in the genus Cahtrar/us, one having large, and 

 the other being entirely vrith out false hoofs. Dr. Sclater must have 

 overlooked this fact when he says, " two other points in which the 

 Pronghorn diifers from all the other Bovidct'" and proceeds, " in the 

 absence of the ' false hoofs,' as the stunted terminations of the rudi- 

 mental second and fifth digits of each foot are termed." (Gray, 

 Ann. & ilag. X. H. 1866, xviii. pp. 468, 469.) 



Pronghorn {Ant'docapra). — " His horns lately seem to have di- 

 verged a good deal ; and upon feeling the base of them it seems likely 

 that they are about to be shed. When this happens the bony core is 

 invested with a hairg sl-in, and the cuticle of the shin [!] hecomcs gra- 

 diudhf thicl-ened and groivs out to become the new corneous sheath, of 

 greater ultimate dimensions than its i)redecessor, until the full size 

 is attained. But in this animal there is no shedding and renewal of 

 the bone, as in the case of the Deer family." — F. Buclland, Land 

 and Wider, Sept. 29, 1866, p. 228. The bony core is always in- 

 vested with a skin, it is only new hair that is developed. 



Fam. 16. ANTILOCAPRID^. 



The bony process of the fi-ontal bone, over the orbit, covered with 

 a porous horny coat, which falls off and is renewed annually. 



The horn or pseudo-horn (komoceras) of the Cabrit is sui generis. 

 It is formed of the matted or felted hair of the skin that covers the 

 core. It loosens and falls ofi' in the mass, when the new coat of 

 matted hair is formed beneath it. The horns may be compared to 

 the annual coat of matted hair which is shed by the American Bison 

 and some other ruminants ; but in that animal the hair only forms 

 a kind of blanket, and falls oflf in flakes of different sizes. 



Antilocapridse, Gray, Aim. S,- Mag. N. H. 1866, xviii. pp. 326, 468 ; 

 Sclater, Ann. S,- Mag. N. H. xviii. p. 403. 



Dr. Sclater also erroneously supposes that, after the horn is pftr- 



