m. Extinct species of American ox. 9 



remaining portion exhibits the same appearances in detail as in the Buffalo, though 

 in an exaggerated degree corresponding to its much greater size (Fig. 2). 



The base of the specimen is very much broken, but that which is preserved 

 indicates the form to have been the same as in the last-mentioned animal. 



The occij^ital condyles are alike in both, and, at their anterior part, advance in 

 a concave manner to the posterior muscular protuberances of the basilar process. 

 Between the condyles and paramastoid, a large deep fossa exists, having at its inner 

 side the foramen condyloideum. 



The foramen magnum occipitis is slightly wider than high, being two inches one 

 line by one inch eleven lines. 



The basilar process in the fossil, at its posterior muscular protuberances, is four 

 inches wide and two inches and a quarter at those joining the body of the sphenoid. 



The OS tympanica has been large and inflated, as in the Buffalo, and a portion of 

 one glenoid articulation remaining in the specimen presents the same form as in 

 the latter. 



Admeasurements. 



Breadth of forehead between the bases of the horn- cores . 15 inches. 

 Height of the inion from the upper edge of the occipital 



foramen . . . . . . . . . 5* '•' 



Circumference of the horn-core at its base . . . 20i " 



Circumference of the horn-core ten inches from its base . 17* " 



As before observed, the fragment of a fossil ox head and molar tooth, described 

 by Dr. W. M. Carpenter, also belong to the Bison latifrons. 



The cranial specimen. Dr. Carpenter states, consists of the frontal bone with 

 portions of the horn-cores. From one broken extremity of the latter to the other, 

 the measurement is fifty-six inches ; the right portion being two feet, the left 

 eighteen inches in length. The base of the horn-cores is seventeen inches in cir- 

 cumference, and at the distance of eighteen inches from the head fourteen and a 

 half inches. The frontal bone is nearly plane, and between the horn-cores, which 

 arise laterally from the same level, is fourteen inches in breadth. The horn-cores 

 are nearly cylindrical ; and from the wood-cut representing the specimen, are 

 directed outwards, a little backwards, and slightly upwards.^ 



The tooth found with the above specimen. Dr. Carpenter observes, is a second 

 true molar of the upper jaw of the left side. The crown is worn down nearly to 

 the fangs, and the characteristic ruminant triturating surface is nearly obliterated. 

 The antero-posterior diameter of the crown is a little over an inch and a half, and 

 the transverse diameter is an inch and a sixth. 



In the cabinet of the Academy of Natural Sciences there are preserved five molar 

 teeth, about one-third larger than those of the Buffalo, which I am disposed to con- 

 sider as having belonged to the Bison latifrons (Plate 11., Figs. 2 — 7). 



' Dr. Carpenter says " forwards," but, from tbc cut, he evidently means upwards. — Am. Journ. of 

 Sd. vol. i. 1846, p. 245. 

 2 



