14 THE AMERICAN BISONS. 
are given in the subjoined table differ from the atlases of domestic cattle 
in the very much greater size of the articular cup, and in the form of the 
pleurapophyses or “wings” of the atlas. 
TABLE I.* 
MEASUREMENTS OF ATLASES. 
a 2 3 4 5 6 a | 8 
i | See 
Transverse axis of = of articular cup Fo oe 133] 137) 133) 128) 115) 117) 1168) 113 
Giermo- dorsal ce ee: 70 65 62| 60 54 57 61 58 
Transv eo axis - a ati SUINACE =. 136] 126) 130] 119} 112} 102) 128) 114 
Greates e breadth of atlas... .-......-...5...... 940 215) 227) 200|...., 170, 237) 204 
ein eomiih Semanal ce ne a a atlis.:.-.:-. TOO, FO. 116) 96). 2) So 105) 97 
Greatest length near the lateral edge of wing.....-..------ 127) 120) 130\ 1151 | 110) 135) 116 
Lengt sth of centr, mesial line of sor aspect Sek ee 59) 51) 50} 55} 54) 50) 53) 47 
TSA Oe es ee S84. 58 © 60...) 66 @4).... 
* The measurements in this and all the following tables are given in millimetres. 
Explanation of Table I. 
Bison latifrons. Darien, Georgia. 
Bison “crassicornis.” Eschscholtz Bay. (Measurements from Richardson.) 
Bison bonasus. Large adult male. (M. C. Z. No. 165.) 
Bison americanus. Large old male. (M.C. Z. No. 10.) 
Bison “priscus?” Eschscholtz Bay. (No. 24,576 of Richardson.) 
Bison americanus. Adult female. (M. C. Z. No. 105.) 
Old domestic bull. 
Domestic ox. (Measurements from Richardson.) 
on oaunr ONE 
From the above table it will be seen that the Georgia specimen is the 
largest of the series; that the atlas of B. “ crassicornis” is next in size, while 
that of B. bonasus is third, though exceeding in some of its proportions either 
of the above-named specimens; the latter differs more from them in its pro- 
portions than does the atlas of the male B. americanus. This, though fourth 
in size, corresponds quite nearly in form with the fossil specimens. The atlas 
of B. bonasus has a considerably greater sterno-dorsal thickness than either 
of the others. The atlas of Richardson’s “ Bison priscus ?” it will be noticed, 
corresponds very nearly in size with that of the female of B. americanus, being 
apparently a little smaller, while from Richardson’s measurements and descrip- 
tion it seems to differ but slightly from it in form. All the parts referred 
by Richardson to his “B. priscus?” except the skull (No. 24,589 of Richard- 
son) and a horn-core (No. 105 of Richardson) correspond in size with similar 
parts of Bison americanus, and seem not to differ essentially in any point 
from them. 
aia 
