6. VESPERTJGO. 207 



l"-6, third finger 2"-7, fifth finger l"-7, thumb 0"-25, tibia 0"-65, 

 foot 0"-35. 



Hah. Khasia Hills, Assam. Type in the collection of the Indian 

 Museum, Calcutta. 



This species is readily distinguished by the peculiar thickness of 

 the lower half of the outer side of the ear-conch, which appears, as 

 it were, excavated out of the thick integument of the neck. The 

 tragus is short, rounded off broadly above and curved inwards as in 

 V. noctula ; but the minute upper premolar, so constant in V. noctula, 

 is absent, and the wing-membrane extends to the base of the toes. 



In the form of the ears and muzzle especially, and generally in 

 the whole conformation, this species appears to belong to the sub- 

 genus Vesperugo ; but the absence of the first minute upper premolar 

 relegates it to Vesjperus. Nothing could Ulustrate better the arti- 

 ficial character of these subgenera, which, however, are convenient 

 in determining the species. 



21. Vesperugo albigularis. 



Vesperugo (Marsipolaemus) albigularis, Peters, MB. Akad. Berl. 1872, 

 p. 260. 



Ears very broad and broadly rounded off above ; the lower half of 

 the outer margin of the ear-conch broadly folded backwards, as in 

 V. noctula, separated in front from the angle of the mouth by a 

 wart, hut terminating heloiv and internal to it lender the loiver jaiv by 

 « snmll intermil prolongation; tragus broad above, attaining its 

 greatest width above the middle of the inner margin, which is 

 slightly concave, narrowest opposite the base of the inner margin, a 

 prominent triangular lobe at the base of the outer margin. Nos- 

 trils rather wide apart, opening sublateraUy ; muzzle broad and 

 obtuse ; crown of the head scarcely elevated above the face-line. 



Wings from the base of the toes ; postcalcaneal lobe long and 

 narrow, last caudal vertebra free. 



Fur dark brown above, the extreme tips hoary, as in V. noctiva- 

 gans, paler beneath, the chin and throat, as far back as a line con- 

 necting the posterior margins of the ears, pure white. 



Upper inner incisors long and broad and slightly bifid at their 

 extremities ; outer incisors very short, scarcely exceeding the cingu- 

 lum of the inner ones in vertical extent ; the single upper premolar 

 close to the canine ; lower incisors in the direction of the jaws ; 

 first lower premolar half the size of the second, which exceeds the 

 molars in vertical extent. 



Length (of the type specimen, an adult c?), head and body 2"'35, 

 taU l"-5, head 0"-7, ear 0"-65 X 0"-4, tragus 0"-25x0"-13, forearm 

 l"-65, thumb 0"-.35, third finger 2"-75, fifth finger 2", tibia 0"-6, 

 foot 0"-35. 



Hab. Mexico. Type in the collection of the Berlin Museum. 



This species may be at once distinguished from all other species 

 of Vespertilionidse by the very peculiar manner in which the outer 



