A MONOGRAPH OF THE BATS OF NORTH AMERICA. 35 



surface, one small ami inconspicuous at junction of internal basal lobe 

 to tbe main portion of tbe auricle; a second, mucb lonj^or, arises bebind 

 tlie tragus and passes upward nearly to the tip. Tbe auricle anterior 

 to the ridge last named is sparsely covered witb bair. Numerous deli- 

 cate transverse folds are seen on tbe outer balf of tbe auricle, Miiicb 

 reacb almost to tbe border. ISearly on aline witb tbe Junction of the 

 external basal lobe and tbe main portion and opposite to tbe meatus a 

 semilunar raised fold is seen. 



The iuterauricular membrane is notched above, hairy on the outer sur- 

 face, and with a longitudinal ridge in young individuals in the middle 

 line. Tbe meml)rane extends beyoiul tbe inner cantbus of tbe eye, at 

 which point it bears a small wart. Tbe tragus is long, slender, and 

 tapering; when laid forward it reaches to the inner cantbus. The 

 posterior surfjice is furnished witb a longitudinal ridge. The base ex- 

 hibits two roots, one extending a short distance obliquely on tbe face; 

 tbe other continuous with tbe ridge opposite to tbe meatus. The 

 tragus is slightly constricted above tbe facial root, but soon becomes 

 convex along tbe inner border. The outer border is straight, ex- 

 cepting at the base. Here tbe parts are variable. In the greater 

 number of specimens examined a trace only of an external basal lobe 

 is seen.* Tbe nose-leaf is simple, entiie, rounded at the muzzle and 

 fixed to the upper lip, while free at the sides. The erect portion tapers 

 acutely, and is sparsely covered with bair. A rudiment of a midrib is 

 seen between tbe nostrils. The nostrils are oblong, oblique, with raised 

 trenchant borders. They are slightly narrowed externall}- and do not 

 modify the lateral contour of tbe nose-leaf. A erescentic patch of warts 

 lies on the face back of the muzzle. Two small, slightly oblique, smooth 

 mental plates, separated by a groove, are seen at the chin. Well back 

 of the chin-plates is a conspicuous median wart. The rictus is on a line 

 witb the inner cantbus. The wing membranes are attached to the epi 

 trochlea.! Tbe fifth metacarpal bone is the longest. 



Tbe prevailing color of the fur is white. On tbe dorsum for tbe apical 

 fifth it is light brown, fawn, or yellow brown. Frequently the extreme 

 tip is gray. On the venter tbe basal half of the hair is alone white, 

 the apical half being ashy-brown, tbe extreme tip again appearing 

 wiiite or plumbeous. The face retains the color of the venter without 

 the basal white. The side of tbe neck and the base of the prebrach- 



*Iii a youug- individual (8916, S. I., the epiphyses not nnited, and the length of 

 the body 14""") the external basal lobe was thick and acutely concave on the outer 

 bord«ir. It was obsiiurely verrucose and received by a delicate told the outer bor- 

 der of the tragus ui)()n its anterior surface. A thickened longitudinal swelling was 

 seen on tlie posterior surface near the inner border. In a second immature speci- 

 men (42""" long, the milk teeth being in position) the tragus was more as in adult. 



tin an immature specimen, No. 4405, Mus. Comp. Zocil., the membrane came from 

 the epicondyle. 



