NO. 2086. 



SOME MAMMALS OF THE PLEISTOCENE— HAY. 



521 



ward above and below to points a short distance behind the socket 

 of the hindermost molar ; on the inner side to a line descending from 

 a point just behind the second true molar. In this jaw are retained 

 the last premolar and the first and second molars. The sockets of 

 the second and third premolars and the last molar are present. 



It is, of course, impossible to determine what was the length of 

 the jaw and the length of its symphysis. The following measure- 

 ments are obtained and compared with corresponding measurements 

 of the jaw of the jersey cow already mentioned and of two female 

 specimens of Bison bison (No. 14099, Amer. Mus., and No. 49680, Nat. 

 Mus.). In the case of the jersey the front milk molar must take 

 the place of the second premolar in the measurements. 



Measurements of lower jaws in millimeters. 



Bison 

 sylvestris. 



B. bison, 

 49680, 



U.S.N.M, 



B. bison. 

 14099, 

 Amer. 



Mus. 



Jersey 

 cow. 



Distance from rear of symphysis to front of socket of the second 



premolar 



Distance from rear of symphysis to rear of second molar 



Distance from rear of mental foramen to rear of second molar 



Height of jaw just behind the symphysis 



Thickness of jaw just behind the symphysis 



Height of jaw at front of socket of premolar 2 



Thickness of jaw at front of socket of premolar 2 



Height of jaw at rear of second molar 



Thickness of jaw at rear of second molar 



62 

 160 

 159 

 23 

 13 

 29 

 16 

 53 

 28 



70 

 180 

 171 



36 



15 



41 



16.5 



61 



27 



56 

 150 



24 

 14 

 31 



17 

 54 



28 



50 

 154 

 158 



26 



14.5 



31 



16 



58 



24 



The following measurements of the lower teeth have been secured 

 from the type-specimen of Bison sylvestris; from No. 14099, a female 

 bison in the American Museum; an old domestic cow, No. 92, in the 

 collection of Mr. S. H. Chubb, of the American Museum; and the 

 already oft-referred-to jersey cow in the United States National 

 Museum. The teeth of No. 92 had been more worn down than in 

 the other specimens, and this fact will account for the reduced length 

 of the grinding faces. 



Measurements of lower teeth in millimeters. 



Distance from front of socket of pm 2 to rear of socket of m 2 



Distance from front of pm 4 to rear of m 2 



Premolar*, height, 



Premolar*, length 



Premolar*, width 



Molari, height 



Molarj, length 



Molar^ width 



Molar 2 , height 



Molar 2 , length 



Molar 2 , width 



Bison 



B. bison, 



No. 



14099. 



Old cow, 



sylvestris. 



No. 92. 



104 



95 



93 



71 



66 



85 



19 



22 



16 



21 



20 



18 



12 



11.3 



15 



20 



25 



15 



22 



23 



22 



13.5 



14.5 



13.5 



34 



30 



23 



26 



24 



23 



17 



15 



14 



Jersey 

 cow. 



104 

 72 



30 

 24 

 13 



46 

 26 



Hi 



