HORNS OF MAMMALIA. 



625 



sinuses extend therein: in Antilopidce the core is solid or but 

 slightly excavated at the base. In an Indian species (Antilope 

 quadricornis, fig. 491) two pairs of horn-cores are developed from 



490 



Skull of Ox with horn-core, a, and horn, b. 



the frontals; the same peculiarity characterised the gigantic 

 extinct Antelopes (Bramatherium and Sivatherium, vol. ii. p. 473, 

 fig. 322), and they also combined the branched character of the 



horn in the hinder pair, which is 

 at present restricted to the single 

 pair borne by the Prong-horn An- 

 telope (Antilocapra Americana, fig. 

 492). 



492 



Skull of four-horned Antelope* 



Branched horns of the Prong-horn, 



In the true Oxen (Bos) the horn-cores spring from the posterior 

 angles of the frontals, fig. 490 : in the Bisons (Bison) their origin 



VOL. IIL S S 



