MAMMALS OF MINNESOTA. 35 



Vespertilio pulverukntus TEMMINCK. Monog. Man., 1835. 



LECONTE. Proc. Acad. Sci., Phila., 1855. 



MAX. v. WIED. Archiv. Naturg., 1861. 

 Scotophilus noctivaqans H. ALLEN*. Monog. N. A. Bats., 1864. 



J. A. ALLEN. Cat. Chir., 1869. 



Vespertilio (Vesperides) noctivagans COUES. Surv. 100th Mer. Zool., 1875. 

 Lasionycteris noctivagans DOBSON. Cat. Mam., Mass., 1878. 



Never having seen a specimen of the silvery-haired bat from 

 Minnesota, I simply quote the description given in Allen's 

 monograph : 



"Head flat, broad and moderately haired; snout naked; nos- 

 trils wide apart, and opening sublaterally; space between 

 emarginate. Sides of face slightly swollen. The auricle is an 

 irregular oval. The inner border extends upwards and in- 

 wards to a level with the top of the head, and then turns up- 

 wards and outwards, ending in an obtuse point. The outer 

 border is smooth, and terminates inferiorly and internally in a 

 thin ridge near the angle of the mouth. The lower half of this 

 border folds irregularly upon itself, and bends so markedly 

 inwards as to touch the tragus. The tragus is straight inter- 

 nally, strongly and abruptly convex externally, narrow at its 

 base. It is but one -third the hight of the auricle, and nearly 

 as broad as high. Skin of face and ears blackish, with the ex- 

 ception of the internal basal lobe of the latter, which is whitish. 

 Fur long and silky, with a marked tendency to become black, 

 and in many specimens the extreme tip of each hair is the only 

 part possessing a different hue it being pale gray or white. 

 The fur is thicker on the back than in front, but the coloration 

 is very similar. The posterior part of the interfemoral mem- 

 brane is thinly covered with short dark colored hairs; the an- 

 terior surface has upon it numerous minute tufts arranged 

 linearly. Thumb small, foot moderate. 



Dentition i. f, c. i, ra. f x2=36. 



Upper incisors closely approximate to but not touching ca- 

 nines, nearly of the same length; median pair bifid, twisted on 

 their axes so that the two cusps have a somewhat antero-pos- 

 terior arrangement; internal cusp slightly longer. Lateral 

 pair unicuspid with a basal cusp. Canines simple and moderate. 

 First premolar very small, unicuspid, second premolar with a 

 very long external and short internal cusp. 



In the lower jaw the incisors are not crowded, trifid. Three 

 premolars, of which the second is smallest. 



