PIPISTRELLE 



irregular, and over large areas it is absent or very rare. It 

 seems to prefer the banks of forested streams or mountain 

 meadows where it appears when twilight has set in. 



This Bat migrates southward from the colder parts of its 

 range upon the approach of autumn and during this time may- 

 be seen occasionally flying during the day. This species 

 spends the day in hollow trees, in dense masses of foliage, or 

 in caves. 



The young may be one or two in a litter. 



Genus Pipistrellus 



Dentition: Incisors, f ; Canines, {; Premolars, f ; Molars, | = 34. 



Pipistrelle. — Pipistrellus subflavus 



and related forms 



Names. — Pipistrelle; various names for the different species, 

 such as Western Bat for P. hesperus. 



General Description. — Among the smallest of the North 

 American Bats; ear of medium size, broad, rounded at tip; 

 tragus straight or slightly curved forward, tip bluntly rounded; 

 interfemoral membrane sparingly sprinkled with hair on basal 

 third of upper surface; membranes blackish. 



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

 ation. 



Upperparts light yellowish brown, underparts very much 

 like upper or slightly paler; pelage everywhere slaty black at 

 base. 



Measurements. — Total length, 3.4 inches; tail vertebras, 

 1.6 inches; hind foot, .32 inch; forearm, 1.3 inches. 



Geographical Distribution. — Eastern United »States. 



Food. — Flying insects. 



Enemies. — Owls. 



Species and Subspecies of the Genus Pipistrellus 



Georgian Bat. — Pipistrellus suhflavus subflavus (F. Cuvier). 

 As described above; ear reaching slightly beyond nostril 

 when laid forward. Found in the eastern United States 

 from Atlantic coast to Iowa and eastern and southern 

 Texas, in Austral and occasional parts of Transition Zone. 



New York Pipistrelle. — Pipistrellus subflavus obscurus Miller. 

 Duller and less yellow than typical subflavtis and with more 



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