482 



THE AGE OF MAMMALS 



Bison. — We owe to Allen (1876)/ Lucas (1899),2 and McClung (1908) ^ 

 our knowledge of the skull and skeleton of the many kinds of great bison, 

 or buffalo, which roamed over all parts of North America during Pleistocene 

 times. As revised by Lucas, there are seven vahd species of fossil bison, 

 which had a widely extended geographical distribution from Florida to 

 Alaska (Fig. 211). They also undoubtedly in part succeeded each other 

 in geological time, the latest bisons culminating in the recent species. Bison 



bison, more or less fossilized 

 remains of which have been 

 discovered in Kentucky, Kan- 

 sas, and in the loess deposits 

 of Missouri. 



The early and gigantic form 

 (B. lotifrons) reflects the favor- 

 al)le conditions of life during 

 the Megalonyx Zone. In 

 Texas, Mississippi, Georgia, 

 Ohio, Kentucky, and Kansas 

 remains of this species have 

 been found. In some of 'these 

 localities they are associated 

 with bones of the American 

 mastodon, the Columbian 

 mammoth, and of the great 

 sloths Megalonyx and Mylodon. The horn cores are so long and thick that 

 they exceed by two feet on each side those of the existing Old and New 

 World bison, as shown in the accompanying figure. Horns in the collection 

 of the Cincinnati Natural History Society measure 6 ft. 6 in. (1.95 m.) 

 along the curve from tip to tip. This measurement is exceeded by the 

 magnificent horn cores discovered in Kansas and secured by Sternberg 

 for the American Museum of Natural History; they measure 6 ft. across 

 from tip to tip, and 8 ft. 6 in. (2.55 m.) along the curve; this appears to be 

 the record in size. Although the skeleton is unknown, we may judge from 

 the size of the skull that B. latifrons far exceeded any of its living relatives. 

 Remains of another ancient form. Bison antiquus, have been found in 

 Kentucky and in California associated with remains of elephants, mas- 

 todons, horses, and camels. Although a much smaller animal, it appears 

 to have been a contemporary of B. latifrons in the Megalonyx life zone, ])ut 

 may have survived to a more recent date. It is considerably larger than 



1 Allen, J. A., The American Bisons, Living and Extinct. Mem. Mus. Comp. Zocil. Har- 

 vard Coll., Cambridge, Vol. IV, no. 10, 1876. 



2 Lucas, F. A., The Fossil Bison of North America. Proc. U.S. Nat. Mus., Vol. XXI, 

 no. 1172, 1899, pp. 755-771. 



» McClung, C. F., Restoration of the Skeleton of Bison ocddentalis. Kansas Univ. Sci. 

 Bull, Vol. IV, no. 10, Sept., 1908, pp. 249-254. 



Fig. 212. — Skulls of (.4) the extinct bison of 

 Kansas, B. latifrons, and of {B) the recent bison of 

 the Great Plains, B. bison. In the American Museum 

 of Natural History. 



