1906.] Allen, Mammals from Western Mexico. 261 



These specimens range in color from pale buffy brown to ochra- 

 ceous. Alar expanse, 254-279, averaging about 267; length (body 

 only), 35-45- 



54. Chilonycteris mexicana Miller. 



Fourteen specimens, Rancho Palo Amarillo, 13 specimens near 

 Amatlan, Jan. 16, 19, 20, Feb. 9; Los Masos, i specimen. All but 

 two are in the dark phase ; the others are more yellowish on the head 

 and shoulders, but only slightly approach the yellow phase, described 

 as "entire head and body tawny ochraceous. " 



Collector's measurements of 5 specimens: Alar expanse, 368 (337- 

 375); length, 61 (60-63). 



55. Pteronotus davyi fulvus (Thomas). 



Three specimens, Los Masos. In one the pelage is bright fulvous, 

 in the others dark brown. 



56. Aello megalophylla senicula (Rehn). 



Two hundred and sixty -four specimens: Rancho Palo Amarillo, 

 near Amatlan, Tepic, 56 specimens, skins and skulls, and 195 salted 

 specimens, Jan. 1620; Ojo de Agua, 4 specimens, skins and skulls, 

 Feb. 9; Los Masos 9 specimens, skins and skulls. 



The series includes about an equal number of males and females. 

 There is apparently no sexual difference in either size or coloration. 

 The species is slightly dimorphic, with a yellowish brown phase and a 

 darker, somewhat dusky brown phase. According to the collector's 

 measurements the alar expanse averages about 368 mm. (352-381), 

 with very few specimens below 362 or above 374; the length averages 

 about 64, ranging from 60 to 70. 



57. Glossophaga mutica Merriam. 



Six specimens, skins and skulls, and 70 salted specimens, Rancho 

 Palo Amarillo, near Amatlan, Jan. 16, 19. 



58. Choeronycteris mexicana Tschudi. 



Eighteen specimens, Los Masos. All are dark brown except one, 

 which is deep fulvous, showing that the species is dichroic. 



59. Dermanura tolteca (Saussure). 



Four specimens: Artenkiki, 2 specimens, near Las Canoas, Sept. 

 16, Los Masos, 2 specimens. 



