1904.] NATURAL SCIENCES 01'' PHILADELPHIA. 207 



Measurements}^ — Total length 62 mm.; head and body 46; ear 

 (from meatus) 15.8; tragus 5; forearm 44; thumb 8; third digit 71; 

 tibia 17; calcaneimi 19; foot 9 (8); tail 16. 



Total length of skull 15 mm.; greatest zygomatic width 8.2; inter- 

 orbital width 3.7; height at base of second premolar 4; height of brain- 

 case 6.5; width of palatal constriction 1.2; length of palate 6; width 

 of palate including teeth 5.5; greatest length of mandible 10.5. 



Remarks. — This species hardly requires comparison ^^'ith any in the 

 genus, being smaller and differing in general aspect from the boothi and 

 ruhiginosa group, while the macleayii type may easily be separated by 

 the form of the ear. The skull closeh^ resembles that of Dermonotus, 

 but it is slenderer with a narrower interorbital region and different 

 shaped premolars. As the species seems to approach Dermonotus in 

 some characters, I have placed it at the end of the genus, all the other 

 forms appearing to l^e more homogeneous, a fact rather strongly 

 demonstrated by the form of the skull. 



Specimens Examined. — One alcoholic; Isthmus of Tehuantepec, 

 Mexico. (U. S. N. M.) 



^^ As some measurements of the only available specimen have already been 

 published by Miller {I. c), I have used his information, only filling out the pro- 

 portions required to make the measurements uniform with those of the remainder 

 of this paper. 



