THE BEETLES 



147 



and with the prothorax greatly widened, giving them the name 

 11 flat-headed borers," which is also often applied to the family. 



They are to be found beneath 

 bark, making irregular cham- 

 bers in the sapwood and in the 

 inside of the bark. Some feed 

 only on dead or dying tim- 

 ber, while others, like the 

 flat-headed apple-borer, attack 

 healthy trees and often cause 

 their destruction. One of the 

 common smaller species is the 

 red-necked blackberry-borer. 

 It is a third of an inch long, 

 with black wing-covers, dark 

 bronze head, and coppery 

 bronze prothorax. The larva bores in the sapwood of the rasp- 

 berry and blackberry, causing a galJ-lik^ swelling, and when full 

 grown bores into the pith, 

 where it pupates. 



The fireflies (Lampyri- 

 dae) which twinkle in the 

 dusk of a warm summer 

 evening are not really 

 flies, but beetles, though 

 their bodies and wing- 

 covers are much softer 

 in texture than those of most beetles. 



FIG. 208. Flat-headed apple-tree borer. 

 (Twice natural size) 



a, larva ; l>, beetle ; c, head of male ; d, pupa 



(After Chittenden, United States Department 



of Agriculture) 



a 



FIG. 209. A firefly beetle (Photinus pyralis) 

 <7, larva ; ^, pupa in cell ; c, adult. (After Riley) 



FIG. 210. Soldier-beetle (Chauli- 

 ognathus pennsylvanicus] 



a, larva ; b, its head enlarged ; c, 

 adult. (After Riley) 



Most of the fireflies are 

 medium-sized beetles, about half an 

 inch long, of dull colors, with the pro- 

 thorax expanded so as to cover the 

 head. They are nocturnal in habit 2 

 the phosphorescent glow being pro- 

 duced by the underside of the ter- 

 minal abdominal segments. Many of 

 the females are wingless and are also 

 phosphorescent, being known as glow- 

 worms. The larvae are predacious. 



