450 Illustrations of the Genera of the Bovince. [No. 114. 



Lumbar vertebrae. The Humerus in Bos, compared with the fore arm 

 is somewhat shorter than in Bibos. The carpus and canon united, 

 compared with the fore arm is shorter in Bibos than in Bos. 



The following comparative peculiarities in all these animals present 

 themselves : — 



The skull and horns are greatly heavier in Bibos than in Bos or 

 Bisonus. The forehead of Bibos is at first sight hollow, but is actually- 

 flat ; the concave appearance being derived from a great transverse arch 

 of bone which surmounts the face ; projecting forwards in some 

 degree, but its direction taken along the convexity parallel with the 

 centre of the horns' cores. The orbit in Bibos projects more than in 

 Bos, or Bisonus : the nasal bones are most arched (transversly) in 

 Bibos, least so in Bos. The face — from anterior margin of orbits 

 to muzzle — longest in Bisonus, about equal in Bos and Bibos. In 

 Bisonus the forehead above the orbits, is transversly arched, in Bos it is 

 quite flat. In Bos, placing the muzzle on the ground, the parieto-frontal 

 junction is flush with the superior aspect of roots of the horns' cores. In 

 Bisonus, placing the skull similarly — the superior portion of the frontal 

 bones is, for about an inch and a half on each side, on a line with superior 

 aspect of roots of horn cores ; the medial portions and frontals are con- 

 siderably elevated, forming a central truncated cone between the two 

 portions already noted as being on a line with superior aspect of root 

 of horn cores. In Bibos again, the skull disposed as above, a large bony 

 arch protruding so as to overhang the forehead runs across from horn to 

 horn, the arch commencing at once from their roots. Viewing the three 

 skulls from the superior margin of the intercornual space, (skulls placed 

 as before with muzzles on the ground) to the foramina magna, the follow- 

 ing differences appear so remarkable in Bibos, as to be alone eminently 

 fitted for at once distinguishing it from the others. In Bos, the entire 

 space from the superior margin of the foramen magnum, to the inter- 

 cornual crest of the frontals, is occupied by the insertions of the nuchal 

 muscles, and it is nearly square (trapezium.) In Bisonus, the same space 

 is an equilateral triangle, and divided into two separate parts. 1st. The 

 truly occipital portion, into the whole of which the nuchal muscles are 

 inserted, formed anteriorly (the muzzle on the ground) by a slightly arched 

 line drawn between the posterior margins of the bases of the horn 

 cores ; and posteriorly by the superior margin of the foramen magnum. 

 2nd. The parieto-frontal portion, of a triangular shape, free from mus- 

 cular insertions, only |th the extent of the 1st portion, and forming the 

 apex of the larger triangle. 



