CHIROPTERA. 809 



those anterior being lost in the specimens. The last premolar is somewhat 

 sectorial in form, having a compressed bnt stout median cusp, a broad 

 heel behind, and a small tubercle in front. The last molar is rather smaller 

 than the others, and with a slight posterior or fifth tubercle. The molars 

 support four tubercles nearly opposite, in pairs, and connected by a diago- 

 nal crest, so that when the crown is worn an S-shaped figure results. The 

 two alveoli in front of the last premolar may have contained each a separate 

 tooth or a single tooth longer than any of the others. The fonii of the 

 true molars is as in the Mesodont genera Aphdlscus^ and Ana])tomorplius, 

 and the simple fourth premolar is also that of the former genus. 



Menotheeium lemueinum Cope. 



Locis citatis. 

 Plate LXVI ; figs. 34-6. 



The last premolar is longer than any of the molars. There are no 

 cingula on the molars, but the transverse crest from one of the tubercles 

 descends to the side of that opposite to it, along the end of the cro-wn. 

 Enamel smooth. Ramus of the jaw rather elongate. 



Measurements. 



M. 



Length of bases of six molars O.O'ioO 



Leugtli of bases of true molars 0120 



Leiigtb of basis of first true molar 0040 



Width of basis of first true molar 0032 



Length of basis of last jiremolar 0052 



Width of basis of last premolar 0030 



Depth of ramus at last premolar 0090 



The animal was about as large as the domestic cat. 



CHIROPTERA. 



The following genus is referred to this order with some hesitation. It is 

 founded upon mandibular rami, which are identical, so far as they go, with 

 the corresponding parts of certain bats, bxit the diagnostic parts are want- 

 ing. I originally referred the genus to the same group as PeratJierium. 



'Eeport Captain Wheeler IV, pt. ii. 

 ■^Hujus Operis., pt. i. 



