262 Annals of the Carnegie Museum. 



Teeth. — Pis. XXXVII-XXXIX. The first and second incisors 

 of the upper "dentition are reduced when compared with 0. longipes. 

 I- is also slightly reduced, while the canine is a little enlarged. P- is 

 less trenchant than in 0. longipes and is more like that tooth in 0. 

 hrachydontus including the fangs coalesced into a single root. P- has 

 a heavy cingulum throughout the internal base of its crown, but is 

 otherwise quite similar to that in 0. longipes. The internal cingulum 

 of P- is also quite heavy, but otherwise the differences from P- of 

 O. longipes are very slight and not worthy of mention, which is also 

 true of P-, while the transverse diameter of the molars are somewhat 

 greater in proportion. 



The position of the lower incisors is quite procumbent; their crowns 

 are fan-shaped and in every respect similar to those of 0. longipes. 

 The lower canine is quite heavy in correspondence with the one above, 

 while back of this tooth there is little or no difference in the dentition 

 from that of other species. 



Measurements of Dentition. Mm. 



Antero-posterior diameter of the upper dentition 232 



Antero-posterior diameter of the upper incisor series 30 



I- antero-posterior diameter at base of crown 5 



I- antero-posterior diameter at base of crown 9 



Canine antero-posterior diameter at base of crown 13 



P- antero-posterior diameter at base of crown 7.5 



P- transverse diameter at base of crown 5 



Antero-posterior diameter of continuous molar-premolar series 130 



P- antero-posterior diameter 14 



P- transverse diameter 6 



P- antero-posterior diameter 17 



P- transverse diameter 10 



P- antero-posterior diameter 17 



pi transverse diameter 16 



M- antero-posterior diameter 20 



M- transverse diameter .20 



M- antero-posterior diameter 23 



M- transverse diameter 21 



M- antero-posterior diameter 27 



M- transverse diameter 23 



Antero-posterior diameter of lower dentition 240 



Antero-posterior diameter of lower incisor series 37 



Lower canine, antero-posterior diameter at base. 14 



Lower canine, transverse diameter at base 9 



Px antero-posterior diameter at base 8 



