A MONOGRAPH OF THE BATS OF NORTH AMERICA. 137 



Gonus DASYPTERUS, Peters. 



naf»ji>leni3, Peters, MB. Ak;id. Berlin, 1870, 904. 



Alalaphd, Peters, MB. Akad. Berliu, 1870, 912; Dohson, Cat. Chirop. Brit. Mus., 



1878, 274. 

 Lasiitrus, H. Allen, Proc. Acad. Nat. Sci. Phila., 1862, 146; Mouog. N. A. Bats, 1864,25. 

 XycHcejus, Cones and Yarrow, Wheeler's Exped., ZoiJl., 1875, 87. 



When I described this form I placed it with Lasiuru.s, out Prof. 

 Peters proposed for it a distinctive generic name, Basypteriis^ since it 

 possesses one premohir only in the upper jaw. In the propriety of 

 making this change I concur. 



o 111 



Dental formula. — Molars-- — premolars ^- — canines — incisors X 2=: 30. 



Diagnosis. — Ears elliptical; tragus incurved, blunt, with a transverse 

 ridge on the outer surface. The internal basal lobe projects backward 

 beyond the internal ridge. Back of ample interfemoral membrane 

 scarcely hairy. The phalanges of the third digit equal in length. The 

 first phalanx of the fourth and fifth finger longer than the second. The 

 olecranon is free behind — the membrane concealing the region of the 

 elbow in front. 



The axis of the paracone of the upper premolar, if produced, inter- 

 secting protocone near at its middle. The upper incisor in contact 

 with the canine. (See N'ycticejtis.) The resemblance of the teeth of 

 this genus to those of Antrozoiis have been already noted. 



The manal formula is as follows : 



Millimeters. 



Second interspace 2 



Third interspace 14 



Four f h interspace 40 



Forearm 40 



1. Dasypterus intermedius (Peters). (Plates xxiv, xxv.) 



Lasiurus intermedius H.Allen, Proc. Acad. Nat. Sci. Phila., 1862, 146; Monog. N. A. 



Bats, 1864, 25. 

 Dasi/pterus intermedius Peters, MB. Akad. Berliu, 1870, 904. 

 Atalapha intermedia Peters, MB. Akad. Berlin, 1870, 912 ; Dobson, Cat. Cliirop. Brit. 



Mus., 1878, 274. 

 Xijcticejus intermedius Cones and Yarrow, Wheeler's Expedition, Zoid., 1875. 



Description. — Ears longer than broad, slightly emarginate i)oste- 

 riorly beneath the tip and without black border. The internal basal 

 lobe as in Atalapha, but projects but little back of the inconspicuous 

 keel. The external basal lobe rounded without basal notch anteriorly. 

 Hem narrow; it is confined to the notch as in Atalapha. The tragus as 

 in this genus; the transverse ridge on the tragus complete. Muzzle 

 and chinplate as in A. ciiierea. Wing membranes with markings ([uite 

 as in Atalapha. A conspicuous muscle-mass lies between the long 

 calcar and the foot. This incloses a muscle as in A. novehoracensis. 



