FIELD BOOK OF MAMMALS 



Myotis spends the day in caves and, when these are not 

 available, in hollow trees or under the eaves and in the roofs 

 of buildings where they are not disturbed. 



Myotis may be seen flying iii a great many environments, 

 but is observed to best advantage at the edge of a forest 

 clearing, over the surface of a lake or a slow-flowing stream, 

 or at the opening of any natural tunnel such as a foliage- 

 enclosed corridor under the trees, under bridges, or near an 

 open shed or bam. This Bat often flies into houses if the 

 doors or windows are open, 



I believe that the Bats of this genus generally have but one 

 young at a birth. 



Genus Lasionycteris 



Dentition.— Incisors, f ; Canines, \; Premolars, f ; Molars, f =36. 



Silver-haired Bat. — Lasionycteris noctivagans (Le 

 Conte) 



Names. — Silver-haired Bat; Silvery-haired Bat; Black Bat. 



General Description. — A medium-sized Bat of dark appear- 

 ance, the hairs tipped with silvery white. Ear of medium 

 size, broad, rounded at tip; tragus short, straight and broad; 

 interfemoral membrane well furred on basal half of upper 

 surface. 



Color. — Sexes colored alike; no noticeable seasonal vari- 

 ation. 



Upperparts dark chocolate-brown tipped with silvery white; 

 pelage long and lax; membranes dark brown; underparts very- 

 much like upperparts but with less light-tipping. 



Measurements. — Total length, 4 inches; tail vertebrae, 

 1.6 inches; hind foot, .32 inch; ear from crown, .6 inch; fore- 

 arm, 1.6 inches. 



Geographical Distribution. — "North America north of 

 Mexico, from the Atlantic to the Pacific; probably not breed- 

 ing south of the Transition Zone." (Miller) 



Food. — Flying insects. 



Enemies. — Owls. 



The genus Lasionycteris is peculiar to North America and 

 only the one species is known. Although this Bat ranges 

 over most of North America its distribution is somewhat 



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