EXTINCT BISONS OF NORTH AMERICA— HAY. 



195 



The following measurements were taken on the teeth (fig. 10). 

 The grinding surface of m.^ stands at a height of about 22 mm. above 

 the fork of the roots; the others at a height of nearly 40 mm. This 

 shows that the teeth are only moderately worn. For comparison 

 there are given in the second column the measurements of the same 

 teeth of Bison bison, No. 22374, United States National Museum. 



Measurements of teeth. 



If comparisons are made between the measurements and illustra- 

 tions derived from remains of B. latifrons found in Ohio and the 



Fig. 10.— Bison eegius. Right upper molaks of type. M' at left. X |. 



corresponding measurements and illustrations depicting the type of 

 B. regius, it will be seen that B. latifrons has the forehead wider 

 by from 20 to 45 mm.; that the horn-cores are of sUghtly greater 

 diameter, but are somewhat shorter, and that they are far less strongly 

 curved. The writer admits that it is possible that these differences 

 may be due to individual, racial, or sexual variation. In the last- 

 named case the Ohio animal might represent the male; the Kansas 

 specimen the female. 



Unfortunately, so far as the writer is aware, no teeth have been 

 found with any horn-cores which belong with certainty to B. lati- 

 frons. Leidy ^ described and figured five large molar teeth of a bison, 

 which, from their size, he regarded as belonging to B. latifrons. They 

 had been found near Natchez, Mssissippi, in association wdth masto- 

 don, horse, bear, deer, megalonyx, mylodon, and a large extinct cat. 

 The measurements of these teeth are given as follows: 



1 Smiths. Contr. Knowl., vol. 5, p. 9, pi. 2, figs. 2-7. 



