i86 



AN ECONOMIC ENTOMOLOGY. 



Fig. 170. 



The flat-head apple-borer, 

 Chrysobothris femorata. — a, 

 larva; 5, pupa ; d, adult. 



wing-covers are nearly smooth or with fine punctulations only, 

 and the larvae also feed principally in conifers. 



In the genus Chrysobothris we have forms that are quite flat- 

 tened above, the wing-covers with irregular depressions and 

 elevations, the prothorax with curved 

 sides and narrower behind. Here be- 

 long most of the troublesome species, 

 including C. femorata, the ' ' flat-headed 

 apple-borer," which, despite its com- 

 mon name, attacks a great variety of 

 trees. The larva makes irregular chan- 

 nels and chambers in the sap-wood, 

 boring into the solid tissues a short dis- 

 tance only, just before pupation, and 

 this describes also the habits of many 

 of the other species of this genus. The 

 eggs are laid on the bark in June or 

 July, and the larvae live from one to 

 three years before coming to maturity. 

 Pupation occurs shortly before the pe- 

 riod at which the adults emerge. 



The genus Agrilus contains species differing from any of those 

 heretofore mentioned by their slender, cylindrical form, the head 

 squarely truncate, or cut off in front, the elytra much narrowed 

 at tip. As a rule, the species are dull 

 brownish-bronze in color, the prothorax 

 sometimes brassy or red-bronzed, and 

 none is better known than the * ' red- 

 necked blackberry-borer," Agrilus rufi- 

 collis, the author of the ' * gouty gall' ' on 

 that plant. The larvae in this genus are 

 unusually long and flattened, the seg- 

 ments strongly marked, the "head" not 

 much wider than the body, and the anal 

 forks distinct, differing in each species. 

 Returning to the blackberry-borer, it is 

 good practice to cut out all galled canes early in spring and burn 

 them. Trimming is done at this time as a matter of regular 

 cultivation, and the galls are then easily seen. No "galled" 



Fig 



Blackberry - cane borer 

 Agrilus ruficollis. — b, larva 

 c, adult. 



