SCOTT : LITOPTERNA OF THE SANTA CRUZ BEDS. 



69 



border of m-; the two outer lobes are of less equal size, owing to the 

 narrowness of the posterior cusp, and the posterior conule is more removed 

 from the cingulum than is the case in the type. This second individual 

 shows that the upper premolars are of the P. australe type, p^ and - having 

 nearly square crowns, with well developed tetartocone, while py is very 

 small and single-rooted. 



Measurements. 



Upper premolar-molar series, length 



" premolar series, length 



Pl, length {i. e., antero-posterior diameter) 



" width (/. e., greatest transverse diameter) 



" width 





P^, length 





" width 





PA, length 





" width 





Upper molar series, length 





Mi, length . 





" width . . . . 





M^, length . 





" width . . . . 





M3-, length . ... 





" width 





Lower premolar series, length 





Py, length . 





" width 





P^, length . 





" width 





P3, length . 





" width 





P^, length . 





" width 





My, length 





" width 





M2, length . 





" width 





Type. 



No. 10. 





.081 





.044 





.009 





.009 





.0105 





.012 





.012 





.015 





.0125 





.017 



•037 



.038 



.013 



.013 



.018 



■017s 



■0135 



.014 



.018 



•017s 



.010 



.012 



.0165 



.018 





■039 





.0055 





.0035 





.010 





.0065 





.012 





.009 





.0125 





.Oil 





.0115 





.011 





.013 





.on 



Localities. — Not given. 



