810 FAMILY XL. LAMPYRILXK 



Putnam and Gibson counties; rare. July 4-September 1. 

 Beaten from flowers of the linden. Tilia americana L. 



Subfamily II. LAMPYRINAE. 



The members of this subfamily have the middle coxas contiguous 

 and the epipleura; wide at the base of elytra. They are divided 

 into two tribes, both represented in the State. 



KF.Y TO TRIRKS Of LAMPYRINAE. 



(/. Head, more or less concealed beneath the thorax; antenna? usually ap- 

 proximate at base ; epimera of rnetathorax long. 



Tribe I. I/AMPYRINI, p. 816. 



aa. Head exposed; antennae widely separated at base; epimera of metatho- 

 rax wide. Tribe II. PHENGODINI, p. 824. 



Tribe I. LAMPYRINI. 



To this tribe belong- our true fireflies, most genera possessing a 

 light-giving apparatus on the hind abdominal segments. The head 

 is deeply immersed in the thorax, the edges of which are usually 

 expanded into a wide, thin margin. The tribe is separated into 

 twelve genera, representatives of eight of which have been taken in 

 Indiana. 



KEY TO INDIANA GKNERA OF LAMPYRINI. 



(/. Antennae with second joint small, usually transverse; head completely 



covered by thorax. 



l>. Antenna? bipectinate, somewhat distant at base, last joint simple ; 

 margins of thorax not flattened. VI. POLYCLASIS. 



bl>. Antennae not pectinate, approximate at base. 

 c. Last joint of antennae elongate, simple. 



il. Eyes small ; light organs feeble; ventral segments without stigma- 

 like pores. 



c. Antenna? very much compressed, not serrate ; second joint very 

 short, transverse. VII. LUCIDOTA. 



ee. Antenna- with second joint one-half as long as third, or near- 

 ly so. 



/. Last dorsal segment of male rounded ; light organs wanting. 



VIII. ELLYCHNIA. 



f/. Last dorsal segment of male bi sinuate and truncate. 



IX. PYKOPYGA. 

 dd. Eyes large, but larger in male than female; light organs well 



developed; male with strongly marked stigma-like pores. 



g. Thorax subcariuate; female with light organs on the sides of 



abdomen. X. PYRACTOMENA. 



(!</. Thorax not carinate, frequently grooved; female with light 



organs on the middle of abdomen. XI. PHOTINUS. 



