THE AMERICAN BISONS. 
fA Lol: 
1. — DISTINCTIVE CHARACTERISTICS AND AFFINITIES OF THE 
BISONS. 
Genus BISON Sith. 
Bos (in part) of many authors. 
Bison H. Smauru, Griffith’s Cuvier’s An. King., V, 373, 1827. 
Urus Bosaxus, Nov. Act. Acad. Nat. Cur., XIII, 2, 427, 1827. — Owen, Rep. British Assoc., 1843, 232. 
Harlanus Owen, Proc. Acad. Nat. Sci. Phila., 1846, 94. 
Bisontina RUvimEYeER, Verhandl. d. naturforsch. Gesells. in Basel, IV, iii, 335, 1865. 
Tux bisons are easily distinguished osteologically from the other members 
of the bovine family by the peculiar conformation of the skull. These dis- 
tinctive features, as Cuvier * long since pointed out, consist in the forehead 
of the ox being flat or slightly concave, while that of the bison is convex, 
though somewhat less so than in the buffalo; in the ox the forehead is also 
quadrate, its length being equal to its breadth, while in the bisons the 
breadth, measured at ‘the same point, exceeds the height in the proportion 
of three to two; in the ox the horns are attached to the extremity of the 
highest salient line of the head, or that which separates the forehead from 
the occiput, while in the bisons the horns are placed considerably in front 
of this line; finally in the ox the plane of the occiput is quadrangular, and | 
forms an acute angle with the forehead, while in the bison it is semicircular 
and forms an obtuse angle with the forehead. The genus Bison, as Dr. J. E. 
Gray ¢ was the first to point out, differs also from Bos in the peculiar form 
of the intermaxillaries, which, as in the genera Poéphagus and Bibos, are short, 
triangular, and acute behind, not reaching to the nasals, as they do in Bos, 
Bubalus, and Anoa. They gradually decrease in length from Potphagus to 
Bison, in which latter genus they are much shorter than in the others. 
* See Ossem. Foss., troisieme édition, Tome IV, p. 109, 1825. 
+ Ann. and Mag. Nat. Hist., Vol. VIII, p. 229, 1846; Cat. Mam. Brit. Mus., Part ITI, p. 16, 1852. 
