132 



University of California Publications in Geology [Vol.9 



bison from Big Bone Lick in which the pattern is complicated as in 

 Hay's figure of B. regius. It seems possible that Allen's specimen 

 was in reality B. anticpius, since the latter has been found in the same 

 locality, and, as will presently be shown, has more complications of 

 the enamel than have Recent specimens of B. bison. 



TABLE II 

 Measurements of Teeth op Upper Jaw 



(3 si 





CO CO 





-* 



tr- 



N 



GO 

 GO 



o 



00 



CO 



CO 

 ,H 





ee 







d 

 • ■ in 





CM 05 



01 





rH 

 CI 





OI 





Length of upper series 













Milk 





of cheek-teeth 169 mm. 



172 158 



172 







161 



series 



144 



Length of premolar 

















series 65 



68 60 



67 



70 





66 







58 















Milk 





Length of molar series 100 



107 100 



107 







104 



78 



89 



Length 20* 



21 



20 



! 



25 





22 







P2 Width 16 



15 



17 





17 







P3 Length 20 



19* 



22 



? 



25 



22 



21 







Ps Width 23 



17 



21 



22 



25 







P+ Length 19 



21 19 



21 



23 



20 



24 





19 



P-t Width 26 



28 25 



? 



25 



26 



21 





21 















Milk 





Mi Length 30 



29 28 



26 



32 



27 



33 



26 



26 



Mi Width 31 



30 28 



f 



25 



29 



27 



19 



24 















Milk 





M-> Length 34.5 



37 34 



35 







36 



30 



32 



M2 Width 33.5 



31 30 



? 







26 



20 



23 















Milk 





Ms Length 36 



39 36 



36 







34 



33 



30 



Ms Width 32 



29 33 



? 







26 



21 



22 



* Approximate. 

















Measurements of upper 



teeth of 



several specimens 



are 



given in 



Table II, the length being- 



measured on 



the grinding 



surface, 



the 



width at the base of the ex 



posed portion 



of the 



crown. 



The length 



and width of the individual teeth, as 



well 



as the length 



of the tooth 



series as a whole, varies considerably 



with 



wear. 



The ] 



ength of the 



tooth decreases very considerably, while the width remains more nearly 

 the same, increasing slightly for a while, then decreasing toward the 

 roots. Comparison with measurements of the teeth of B. bison (U. C. 

 M. V. Z. 5597) which exhibit approximately the same degree of wear 

 as 21185, shows that the upper teeth of B. antiquus are considerably 

 larger. The structure of the upper premolars does not differ in any 



