>r 



THE AMEEICAK BIS0:N'S. 



4 



*' Carpus ■ — Metacarpus 

 Kadius (Aussenseite) 

 Humerus mit Trochanter 

 Scapula vorderer Eand 

 Metacarpus mit Kaviculare 



Tibia aussen 



Femur mit Trochanter 



Bison americanus. 

 1. 



1,102^ 3.387 (1 

 1.285 

 1.795 

 1J51 



1.379 )> 3.999 (1.180) 

 1.469 



B. europseiis. 

 1. 



1.254^3.697 (1.) 

 1.443 



,843 



1.098 



1.588^4.489 (1.214) 

 1.803 



79 



Takino- the same method of comparison with five specimens of B. america 



7tiis and two specimens of B, 



(=: eiiropceus) as a basis^ gives propor- 



tions not differing essentially from Riitimeyer's, though the figures range 

 ten to fifteen per cent larger^ being probably based on larger specimens. 



k 



Carpus and Metacarpus 



Kadiu 



3 



Humerus (with Trochanter) 



Scapula 



Metacarpus 



Tibia 



Femur (with Trochanter) 



1. 



1.260 > 3.680 (1.) 



L420 



1.940 



1.400 



1.680 J> 4.800 (1.130) 



1.720 



1. 



1.327 y 3.901 (1 



1574 



1.836 



1.364 



1.727^4.834 (1.15 



.743 



The differences between the two species in these proportions are very 

 slight^ scarcely greater in fact than occur between different individuals of 



Bison americanus. 



t 



Dr. J. E. Gray placed the aurochs and American bison in different sections 

 of the genus Bison^^^ first of which, containing the aurochs^ is character- 

 ized as having the 'Harsi elongate, fore and hind quarters subeqnal/' and the 

 other, containing the American bison, as having the " tarsi short, hinder 

 quarters very low." In the description of the aurochs he says again, " fore 

 and hind legs subeqnal ; tarsi elongate," contrasting it with " tarsus short, 

 hinder quarters very low," in his diagnosis of Bison americanus. The differ- 

 ence in height between the fore and hind quarters of the aurochs and 

 American bison is, as already shown, more apparent than real, owing to the 

 greater size of the pelvic region in the aurochs. The difference in the 

 relative length of the tarsus is also much less than one might infer from 

 Dr. Gray's diagnosis. 



In Bison americanus the proportional length of the metatarsal bone to the 

 length of the femur and tibia taken together is (in five specimens) as 29-31 



^^■^_l-" 



to 100; in Bison honasus (two specimens), as 28 to 100, showing an actual 

 slightly greater length of the metatarsal segment in Bison americanus. The 



