4O WALTER N. HESS. 



contained only a small amount of moist filter paper, while others 

 contained earth and moss. Since no reference was found to a 

 published account of the nature of the mouth-parts of any of our 

 native firefly larvae, these structures were figured in order to 

 better illustrate the method of feeding of these larvae. 



The following species were studied: Photinus consanguineus 

 Lee., Photinus scintillans Say, Photurus pennsylvanica DeGeer 

 and Pyropyga fenestralis Mels. 



The author is indebted to Dr. James G. Needham, Dr. William 

 A. Riley and Dr. O. A. Johannson, under whose supervision the 

 greater part of this study was made, for their helpful suggestions 

 and criticisms. 



HISTORY OF BIOLOGICAL WORK ON LAMPYRIDS. 



Although many workers, both in this country and in Europe, 

 have studied the light-organs of the fireflies, comparatively little 

 has been done on the biology of this group of insects. 



Newport (1857) studied the life-history of the glow-worm, or 

 larva, of Lampyris noctiluca. He not only discussed the de- 

 velopment and general habits of these larvse, but he also per- 

 formed several experiments to determine the nature of their 

 feeding habits. 



Hudson (1891) published an interesting account of the habits 

 and life-history of the New Zealand glow-worm. 



Barber (1905, 1914) described the egg-laying habits of Phen- 

 godes, together with certain habits of this group of fireflies. 



Bongardt (1904) published a brief account of the biology of 

 certain European Lampyridse. 



Knob (1905) described the habitat, flight and light-emission 

 of Photinus scintillans and Photurus pennsylvanica. 



McDermott (1910, 1911, 1912, 1914) studied especially the 

 nature of the flashing of fireflies, together with the attraction 

 of the sexes by means of light-emissions. 



Olivier (1911) described the distinguishing structural char- 

 acters of the common species of fireflies. In addition, he dis- 

 cussed their general habitats and distribution. 



Mast (1912) studied the sexual attraction of fireflies (Photinus 

 pyralis ?) with special reference to their orientation. He found 



