THE AMERICAN BISONS. 9 



• 

 the cranial fragment with its attached portion of horn-core is almost a 

 repetition of the corresponding part of the .skull of the buffalo. The base 

 of the horn-core is situated five inches in a curved line outwards and for- 

 wards, or two inches and a half in a straight line, in advance of the position 

 of the occipitoparietal crest. The forehead is slightly more flat antero- 

 posteriorly than in the buffalo, arising from the occipitoparietal crest being 

 a little less below its level. The lateral margins of the inion are broken 

 away in the specimen, but the remaining portion exhibits the same appear- 

 ances in detail as the buffalo, though in an exaggerated degree correspond- 

 ing to its much greater size. 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 occipital 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 paramas- 

 toid, a large deep fossa exists, having at its inner side the foramen condy- 

 loideum. 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." 



The additional measurements given by Dr. Leidy are as fullows : — 



Breadth of forehead between the bases of the horn-cores, 15 inches, or 380 ram. 

 Height of the inion from the upper edge of the occipital foramen, 5h inches, or 140 mm. 

 Circumference of the horn-core at its base, 20i inches, or 520 mm. 



" " " ten inches from its base, 1 7 A inches, or 445 mm. 



This specimen is still in the museum of the Academy of Natural Sciences 

 of Philadelphia. Through the kindness of the curators of the Museum I was 

 enabled recently to examine the specimen at my leisure. I found the cir- 

 cumference of the horn-core fourteen inches from the base (the point at 

 which it is broken off) to be sixteen inches, or only four inches and a half less 

 than at the base, and three and a half inches less than at ten inches from 

 the base. Mr. Peale, in his description of the same specimen nearly three 

 fourths of a century ago, expressed his belief that " the horn itself could not 

 have been less than six feet in length," and thought it " a reasonable con- 



