1916 J Merriam: Fauna of Cedar Mountain Region 177 



Rodentia 

 DIPOIDES, near TORTUS (Leidy) 



Several specimens from Stewart Valley (locality 2027) represent 

 a form near this species. (See figs. 11 to 13.) 



Measurements 



No. 19802 D. tortus D. curtus 



Length of lower premolar series 17.5 19.5 14.5 



Pi, greatest anterposterior diameter 6.5 5.5 4.6 



P 4 , greatest transverse diameter 4.8 4.7 3.8 



Depth of jaw below M„ 9.5 14. 8.5 



13 



Figs. 11 to 13. Dipoides, near tortus (Leidy). Cedar Mountain beds, Stewart 

 Valley, Nevada. 



Fig. 11. Mandible with P 4 , no. 19802, X 2; tig. 12, P 4 , no. 19804, X 2; fig. 

 13, P 4 , no. 19803, X 2. 



M YLAGAULTJS ?, sp. 

 A fragment of a large molar (no. 19801) from Stewart Valley 

 (locality 2027) represents a mylaganlid form, but the tooth is too 

 imperfect for specific determination. The specimen does not appear 

 to differ distinctly from the fourth premolar of Mylagaulus, and may 

 be referred provisionally to that genus. 



APLODONTIA ?, n. sp. 



A single upper premolar, no. 19798 (fig. 14), from Stewart Valley, 

 (locality 2027) represents a rodent evidently belonging in the group 

 of the Aplodontidae, but not corresponding exactly to any form known 

 to the writer. It shows resemblance both to Meniscomys and to 

 Aplodontia, but does not duplicate the characters of either. 



The crown of the tooth is worn down close to the large, very 

 slightly divergent roots upon which it is supported. On the occlusal 

 face there are at least four enamel lakes, which extend down almost 

 to the lower end of the crown. 



The form of the crown, taken with the depth and the tendency to 

 cylindrical form of the enamel lakes, suggests that the normal unworn 

 crown was short hypsodont. 



