248 Hahn—A Neiv Bat From Mexico. 



Interfemoral membrane sparsely furred at base. Wing membranes from 

 the ankle directly opposite the calcar. 



Sknllniid Teflli. — Theskull is small with ashort broad rostrum, and hitih, 

 strongly rounded braincase. The palate is wide posteriorly, narrowed an- 

 teriorly; posterior palatal projection short and broad. Audital bullae small ; 

 basisphenioid pits deep. The teeth are small and the toothrows short, that 

 portion behind the anterior premolar being so strongly divergent as to form 

 a noticeable angle with the line of the anterior portion. 



Measurements. — Type : * Forearm, 39 ; hind foot, 13 ; calcar, 7 ; ear from 

 base, 16; ear from notch, 13 ; nose leaf without horse shoe, 6.5. Skull of 

 type: Greatest length, 21; basal length, 16.5; greatest breadth, 11; greatest 

 depth, 9.5 , interorbital breadth, 5 ; upper toothrow, 7. 



Remarks. — Hemiderma subrufam is a well marked form which does not 

 appear to intergrade with any other knf)wn species. In size it is interme- 

 diate between the Hemiderma cinilaneiun of H. Allen and the large Mexican 

 species called aztecn by Saussure.t Tlie body is small and the limbs slender 

 and short (forearm 39 as compared with 42 given by Saussure). It also differs 

 markedly in cranial characters from azteca,the skull being not only shorter 

 and smaller but of a very different aspect, the braincase rising abruptly 

 above the level of the rostrum, its sides flaring out in a broadly rounded 

 arch and the palate and rostrum being relatively much broader. The teeth 

 also are much lighter ; thetoothrow is shorter by a milliuieterand the rela- 

 tive proportions of the cusps of some of the teeth differ markedly. 



In addition to the type series from Oaxaca, I have examined specimens 

 in the collection of the Field Coluinlnan Museum from Achotal, Vera Cruz, 

 which do not appear to differ in any essential way from the type. The 

 color is perhaps a little paler but this is an extremely variable character in 

 this genus, in which distinct dichromatism exists. 



* Measurements taken from dry skin. 



t Caroi7ta as/eca Saussure, Rev. et Mag.de Zool. 1860, p. 48i'. Temperate and trop- 

 ical Mexico. 



