24 THE AMERICAN BISONS. 



says Richardson, " the aurochs, or Bison prisms of more recent palaeon- 

 tologists." * To this form Dr. Richardson referred also a large horn-core, 

 an atlas, several Other cervical, dorsal, and lumbar vertebra', a sacrum, 

 parts of several innominate bones, two humeri, several radii, several im- 

 perfect femora, and several metatarsals, chiefly on account of their large 

 size. These remains, together with other bison remains of smaller size, were 

 all from the ice-cliffs of Eschscholtz Bay, the smaller remains of this collec- 

 tion being provisionally referred by Dr. Richardson to "Bison prisons?" The 

 remains referred to Bison crassicornis are described in great detail by Dr. 

 Richardson (the more important of which are also figured), and seem to 

 differ in no important particular (except in being somewhat larger) from 

 the corresponding parts of Bison americanus. Many of the slight differences 

 he points out as existing between bis Bison crassicornis and B. priseus? relate 

 only to what would normally be included within the range of individual 

 and sexual variation of representatives of the same species. All of the 

 remains of his " Bison priseus ?" are smaller, with perhaps the exception of. 

 the fragment of a skull (No. 24,589 of Richardson's work, figured in his 

 plate vii), than the corresponding parts of the male of Bison anirrkanus, 

 some, perhaps of not fully grown individuals, being not larger even than 

 the corresponding parts of the female of that species. The differences exist* 

 ing between the remains referred by Richardson to •• B. priseus?" and " B. 

 crassicornis" are not greater than those that obtain between the two sexes of 

 Bison americanus; hence it seems possible that all of the bison remains 

 described from Eschscholtz Bay may belong to one and the same species, 

 the larger representing the male and the smaller the female, of the form 

 Richardson named Bison crassicornis, which is very probably the same as the 

 B. antiquus of Leidy, and to which the California bison remains may be at 

 least provisionally referred. 



To the same form I at first referred with much hesitation the bison 



remains recently discovered by Mr. Dall ami others in Alaska. As these 



are passing through the press an imperfect skull t from the vicinity 



of St. .Michael'-.. Alaska, has al-o come to hand which seems to Confirm the 



• ZooT "f Voy. "f Herald, aa cited aboye. 



t Beceived f"r examination fmm tin- California Academy of Science) and labelled "Biton am/namm, 

 St. Michael'*, Alaska, presented bj the Alaska Commercial Company." Ii is wholly unminenlited, and 

 ttbered appearance, I>»>kiic_' u a specimen might alter only a f'« yean' exposure to 

 tin- elements. 



