FIELD BOOK OF INSECTS. 



yellow, and the yellow area of the elytra is crossed by a 

 black band, which is very wide in typicum. 



Celetes basalis is about .3 in. long; color much as in 

 Lycostomus later aiis but the elytral yellow much reduced. 

 The antennae, especially of the male, are decidedly comb- 

 like (feathered on one side). 



Ccsniella dimidiata is apt to be confused with Calopteron 

 terminate but its antennas are comb-like, not merely saw- 

 toothed. 



Eros. Most of the species of this genus, and also of 

 Plateros and Calochromus, are black, with yellow-mar- 

 gined pronota. However, E. aurora has scarlet elytra; 

 the under surface of the body is black. 



The subfamily Lampyrinae contains the luminous 

 species. The middle coxae touch each other; the elytra 

 are not reticulate (netted) ; and the head is nearly, or quite, 

 covered by the pronotum. The Lampyrini usually have 

 the bases of the antennas near together. Of the Lampyrini, 

 all except Photuris have the head completely covered by 

 the pronotum and the second joint of the antennae small. 

 Polyclasis is the only genus of this tribe having pectinate 

 (comb-like) antennae, and in it there are pectinations on both 

 sides. In Lucidota, Ellychnia, and Pyropyga the eyes are 

 small and the light-organs are feeble. For the most part, 

 they are black species with yellow on the pronotum. In 

 Pyractomena and Photinus the eyes are large, but larger in 

 the males than in the females and the light-organs are 

 well developed. Pyractomena and Photinus are dark 

 brown, or black, with yellow on the pronotum and margins 

 of the wings. These yellow margins are particularly 

 pronounced in Pyractomena angulata; the narrow-margined 

 forms are not easily differentiated. The females of 

 Pyractomena have the light-organs on the sides of the 

 abdomen and those of Photinus have them on the middle. 

 Pyractomena angulata is not usually common but is very 

 brilliant. Pyractomena ecostata is usually found about 

 marshes, its larvae probably living on snails. Photinus 

 marginellus and scintillans (Plate LXXVIII), are very 

 common. The males fly low and have a yellow light. The 

 females have only partially developed wings and do not fly. 



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