Vol. XXXVIII. February, 1920. No. 2. 



BIOLOGICAL BULLETIN 



NOTES ON THE BIOLOGY OF SOME COMMON 



LAMPYRID^:. 1 



WALTER N. HESS. 



CONTENTS. 



PAGE 

 Introduction 39 



History of Biological Work on Lampyrids 40 



Photinus consanguineus 41 



Photinus scintillans 44 



Photurus pennsylvanica 49 



Pyropyga fenestralis 67 



Purpose of Luminosity 72 



Economic Importance , 73 



Summary 73 



Bibliography 75 



INTRODUCTION. 



The fireflies (family Lampyridse) are among the most common 

 of insects, yet because of the larval habits of most species, com- 

 paratively little is known regarding them except what has been 

 learned from a study of the adults. The larval forms are rarely 

 seen, as most of them are active only at night, and usually are 

 found on, or in the ground, in damp or marshy regions. 



The insects were observed both in the field and in specially 

 prepared large plant-pots at the insectary. These pots were 

 filled about half full of rich mellow earth on which was placed a 

 small amount of moss. Some of the pots were covered with 

 glass, while others were covered with cheese cloth. Since ovi- 

 position occurred very readily in captivity, eggs were obtained 

 for a study of the incubation periods of the different species, by 

 confining ripe females in small jars that had been partially filled 

 with earth. For a study of the feeding habits of the larvee and 

 adults, these insects were confined in glass jars, some of which 



1 Contribution from the Entomological Laboratory of Cornell University. 



39 



