THE FIREFLY FAMILY. 



Photuris (see above) pennsylvanica about .5 in. long, 

 or a little longer; head and pronotum dull yellow, the 

 latter with a central red area crossed by a narrow median 

 dark stripe; elytra brownish, with pale markings (Plate 

 LXXVIII). This is the largest and most brilliant of our 

 common fireflies. Photuris frontalis is similar but smaller. 

 Both have a greenish light. 



The males of Phengodes, a genus, which has been placed 

 in both Lampyrinas and Telephorinas, are not luminous 

 but the larvae and wingless females, which usually live 

 under stones, are the most brilliant of our forms, giving 

 off light from lateral joints along the body. They are 

 usually rare. The males may be recognized by their 

 resemblance to the species shown in Plate LXXVIII. 



The subfamily Telephorinas differs from the Lampyrinae 

 in not having the head at least partly covered by the 

 pronotum. None of the species are luminous and the 

 sexes are much alike. For the most part, they are black 

 or brownish, with more or less yellow on the head and 

 pronotum. 



In Podabrus modestus the pronotum is all yellow; elytra 

 narrowly margined with yellow; legs black. 



In Telephorus rotundicollis the head, pronotum, and 

 legs are reddish; elytra, dark gray-brown. 



Chauliognathus pennsylvanicus (Plate LXXVIII) and 

 C. marginatus are called Soldier Beetles. "The species 

 of this genus are known from all others by the elongate 

 head, and by the singular structure of the maxillary lobe, 

 which has a long, extensile, pilose, thread-like process 

 which can be pushed out and used to gather food. In 

 this respect it is somewhat similar to the tongue or pro- 

 boscis of a moth or butterfly. The mature beetles are 

 said to feed solely upon the honey and pollen of various 

 flowers. The larvae are, however, strongly carnivorous, 

 those of our common species being very beneficial in that 

 they feed upon the larvae of the plum curculio and other 

 injurious forms." The two species mentioned above 

 may be separated by the facts that in pennsylvanicus 

 the pronotum is wider than long and the head black, while 

 in marginatus the pronotum is longer than wide and the 



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