1887.] ^*^^ [Cope. 



neck and fore legs would not exclude it from that family. It is merely an 

 adaptation for the habit of browsing on the foliage of tall trees. In the 

 extinct species of its single genus, GirafFa, these characters are found in a 

 less degree than in the existing one. The most obvious distiucliou between 

 the BoviD^ and the Cervidie is in the differing character of the bony pro 

 cesses of the skull, used for ofiense and defense. But where horns are 

 •wanting, as is the case with some genera, these distinctions fall to the 

 ground. The horn-type of the Bovidte is more primitive than that of the 

 Cervidaj, since the horny process is permanent in the former, and is shed 

 and reproduced annually in the latter. The dental type is, however, 

 never so specialized in the deer, as is the case with the nighcst genera of 

 Bovidse, remaining always distinctly rooted, while in Bos and some other 

 genera of the latter they become prismatic. But the lower genera of 

 Bovidse do not differ from Cervidae in this respect. 



In accordance with these fixcts the bovine ruminants appear a little be- 

 fore the cervine, though authors generally refer the earliest genera to the 

 latter division. Such are the genera Dicrocerus and Cosoryx,* which 

 appear in the latest Miocene beds. Dicrocerus only diflers from Palae- 

 omeryx in the possession of horns, which resemble those of deer, but 

 which were, according to Schlosser, never shed, a fact which compels its 

 location in the Bovidie. In Cosoryx the horns have the same charac- 

 ter in this respect, but the teeth are antelopine, or prismatic. It is clearly 

 to be placed in the Bovidai with Antilocapra (the prong-horn), and it is 

 closely allied to Dicrocerus. Here we see that the point of origin of the 

 two families was from a common ancestor, and that this ancestor was, as 

 has been -already expressed by Schlosser, the genus Pala^omeryx. Nearly 

 related to this point of departure are the Sivatherium, Bramatlierium, and 

 Hydaspidotherium. As they do not shed their horns, they cannot be re. 

 ferred to the Cervidse. In their covering with the integument, Cosoryx 

 probably possessed a character of Giraffa, which is a primitive stage of the 

 essential character of the horns of the Bovidix;. Perhaps the retention of 

 the primitive dermal character of this investment, instead of its metamor- 

 phosis into horn, might be regarded as a basis for a distinct family, the 

 CosorycidfB. But it is highly improbable that this covering remained in 

 Sivatherium and Bramatherium, whose horns were apparently perfectly 

 naked. It is doubtful whether all these animals can be retained as distinct 

 from the Bovidaj, and I therefore place them in two subfamilies of that 

 family. The Cosorycinaj, which will include Cosorj'x and Blastomeryx, 

 are characterized by the sheath of the horns being dermal ; the Sivathe- 

 riinne by the absence of any sheath whatever. The synopsis of genera 

 will then be as follows : 



I. No horns in the male. 

 Molars brachyodout Fakeomery.v\ Von Meyer. 



* Leidy, Cope ; Procervulus Gaiidry. 



t Should P. eminens, type of Palceomeryx, have possessed horns, as suspected by 

 Schlosser, the generic name must take the place of Dicrocerus below, and be replaced 

 by one of the various names which apply to hornless species. 



