266 



Beetles 



FlG. 365. A flat- 

 headed borer, 

 larva of Rha- 

 gium lineatum. 

 (Natural size.) 



Buprestidae, of which over two hundred species occur in North America. 

 The adult beetles have an elongate body, trim and compact, with a rigid 

 and armor-plate-like cuticle, and have iridescent metallic coloring. Green, 

 violet, reddish, blue, copper, golden they may be, always shining like 

 burnished metal and the whole body looking as if cast in bronze. The 

 antenna; are short and serrate on the inner margin, the head deeply inserted 

 in the thorax, and the latter fitting closely against the 

 abdomen and wing-covers; and the second and third 

 abdominal segments are rigidly fused. These beetles are 

 diurnal, running actively on tree-trunks or resting on 

 flowers; seeming to delight in the warm bright sunlight, 

 in which their resplendent colors flash and glance like 

 jewels. 



The larvae are mostly wood-borers, although those of 

 some of the smaller species mine in leaves or live in galls. 

 The wood-boring Buprestid larvae are characterized by the 

 strangely enlarged and flattened, legless, first thoracic 

 segment, on which the small head with its powerful jaws 

 sets in front, and the tapering, flattened, legless, meso- 

 and meta-thoracic segments behind. The abdomen is 

 elongate and rather narrow, the segments showing dis- 

 tinctly. The whole larva (Fig. 365) is thus a footless whitish tadpole-like 

 grub, expressively known as a flat-headed or hammer-headed borer. The 

 larvae that do not burrow in wood are cylindrical and have three pairs of legs. 

 The most injurious Buprestid is the notorious flat-headed apple-tree 

 borer, Chrysobothris jemorata (Fig. 366), an obscure bronze or greenish- 

 black beetle about half an inch long. The legs and 

 under side of the body are of burnished copper, and 

 the antennae green. The eggs are glued to the bark 

 under scales or in cracks; the young larva on hatching 

 eats inward through the bark to the sapwood and 

 there burrows about, sometimes quite girdling the tree. 

 Later it bores into the solid heart-wood, working up- 

 ward and then again out into the bark, where it forms 

 a cell in which it pupates, issuing as an adult in just 

 about one year from the time of its hatching. This 

 pest attacks peach- and plum-trees and several forest- 

 and shade-trees as well as the apple-tree. It ranges 

 over the whole country. To prevent the egg-laying on the bark, the lower 

 trunk of the tree should be washed with fish-oil soap during June and July. 

 When borers are once in the tree, cutting them out is the only remedy. 

 The genus Agrilus contains a number of species having the head flatly 



FIG. 366. Apple-tree 

 borer, Chrysobothris 

 femorata. (Twice 

 natural size.) 



