5O WALTER N. HESS. 



According to LeConte (1851) it is abundant in every part of the 

 United States. Blatchley states that it is the most common 

 firefly in Indiana. Williams also makes a similar statement for 

 Massachusetts. 



As is characteristic of our luminous fireflies, the adults of this 



FIG. 3. Phoiurus pennsylvanica male. 



insect are usually found active only at night. Like many other 

 insects, this species has well-defined centers of distribution, 

 being rarely found except along marshy or moist localities. 

 This, however, is more characteristic of the larvae, but as a rule 

 the adults are found comparatively rarely outside of such regions. 

 They were found most abundant in the City Cemetery, on Stewart 

 Avenue, and in the Renwick marshes, at Ithaca, New York. 

 The cemetery, while not in any sense marshy, has been filled in 



