
748 The American Naturalist. [August, 
have so far found no other of the genus except érast/iensis, which is 
extremely numerous here, as well as in several other parts of the country 
where I have collected. j 
The specimen under consideration appears to be more closely allied 
to W. macrotis than to any other described species, but quite ‘distinct 
from this, as will appear by a comparison of the figures and description 
here given with Dobson, Catl. Chiroptera in Brit. Mus., pp. 435, 439, 
Pl. xxu., Fig. 6. 
Above, burnt umber ; below, Prout’s brown ; bases of hairs on both 
surfaces, white. Membranes and ears, in the alcoholic specimen, 
nearly perfectly concolor with the under surface of body. A line of 

Pig 4 Rig.5. 
Nyctinomus depressus. 
very short hairs bordering humerus and radius on upper surface of ante- 
branchial membrane, so fine as scarcely to be perceptible when wet. 
On upper surface of wing membrane, short lines border the radius, 
except at the extreme elbow, and occupy the angle formed by the 
juncture of the fourth and fifth metacarpals. On both upper and 
lower surfaces the membrane is covered with hairs to a line extending 
from the proximal third of humerus to the middle of the femur. Inter- 
femoral membrane covered for three or four millimeters below femora 
on upper surface, and naked on lower. Inner edge of ear evenly 
convex when flattened out, but from its vertical waviness appearing as 
in Fig. 5. The forward interior margin is reflexed over the deep 
depression at the upper extremity of the keel, thus forming a sort of 
pocket. Outer margin bilobate, the lower lobe arising from a short, 
straight base coming up from behind the antitragus, the upper lobe 
being continuous with the tip and inner edge. Keel large, strongly 
reflexed at angle near base, extending slightly exterior to the antitragus. 
Tragus straight on inner and upper margins. Outer margin formed by 
two slightly concave lines producing a slight lobe by their juncture at. 




