External Characters of Ruminant Artiodactgla. 455 



produced into a short tube free from the terminal cushion- 

 like thickening of the glans, as in Poephagus (cf. infra). 



Genus Bison, H. Smith. 



Bison, II. Smith, Griffiths, Au. King. v. p. 373(1827): type, bison, 



Linn. 

 Bonasus, Wagner, Schreb. Sang., Suppl. iv. p. 515 (1844) : type, 



bonasus, Linn. 



The rhinarium (fig. 2, A, B) differs from that of Bos and 

 Bibos in being more overgrown with hair both above and in 

 front. In front the hair of the upper lip spreads towards 

 the middle line along the lower margin of the nostrils and 

 even penetrates the inner portion of those orifices. Hence 

 at this level the rhinarium is not wider than the internarial 

 septum. Interiorly, however, it expands, and is broad where 

 it passes into the a\ge of the upper lip. Dorsally the hair 

 of the nose spreads over the upper surface of the rhinarium 

 almost to its anterior margin, leaving a comparatively narrow 

 naked rim bordering the nostrils above, so that from the 

 anterior aspect the upper edge of the rhinarium does not 

 present the evenly convex upper margin seen in Bos and 

 Bibos. 



The feet also differ from those of the two last-mentioned 

 genera in having the interlingual web overgrown with hair, 

 which is sometimes stuck together with secretion. This 

 hairy clothing has been observed in two pure-bred specimens, 

 male and female, which died at different seasons of the year. 

 Hence it may be inferred that the growth of hair on this 

 part of the foot is not a seasonal character, as it appears to 

 be in some of the Caprine Ruminants — e. g., Ammotragus 

 lervia and Ovis musimon *. 



The penis (fig. 4, F, G), like that of Bos, has no free 

 prolongation of the urethral canal. 



Although I have cited Bonasus as a synonym of Bison, it 

 must be explained that that course is justified mainly by 

 inference, since I have had no opportunity of examining 

 fresh material of the European species, B. bonasus, which is 



* Some of the American bisons that have been imported into England 

 as pure-bred stock appear from the higher carriage of the head, higher 

 quarters, longer horns, and other points to have tai/rus-h\ood in their 

 veins. They are hybrids known as cattaloes in the United States. One 

 of these had the interlingual integument of the hind feet naked as in 

 Bos taunts, whereas the interlingual skin of the fore feet was covered 

 with a growth of short hairs, being intermediate in this respect between 

 the naked condition seen in B. taurus and the loug-haired condition seen 

 in Bison bison. 



