CLASSIFICATION AND DESCRIPTION OF COMMON INSECTS 293 



segment marked crosswise with a broad yellow band and many short 

 white hairs. Feeds on heads bearing the berries. 



Pupa. — Yellowish, formed in an earthen cell in the ground, where it 

 winters. 



Control. — Spray with arsenate of lead, 3-4 lb. to about 40 gal., where 

 beetles first appear. 



SILPHID^ (CARRION BEETLES) 



Spinach Cairion Beetle {Silpha biiuberosa Lee). — The shiny black 

 active flattened larva of this dull black beetle destroys the leaves 

 of spinach, pumpkin, squash, beet, etc. at night. Eggs are laid in 

 June and the grubs mature four or five weeks later. The adult beetles 

 winter under clods, etc. 



S. opaca L. is also an injurious species in the West. 



ELATERIDiE (CLICK BEETLES, WIREWORMS) 



Comnion Economic Genera (After Leconte and Horn) : 



A. Hind coxal plates suddenly dilated about the middle, the outer part much 

 narrower than the inner. 

 B. Prosternum very broad, sutures straight, side pieces of meso thorax 

 reaching the middle coxas. — Cryptohypnus. 

 BB. Prosternum of moderate width; sutures double and not excavated in 

 front; third joint of antennae longer than second. — Drasterius. 

 AA. Hind coxal plates gradually dilated on the inner side. 



B. Clypeus or front convex and truncate, its edge higher than the lab rum, 

 mouth inferior and applied to the prosternum in repose. Side mar- 

 gins of thorax bent downward in front. — Agriotes. 

 BB. Clypeus or front flattened; mouth horizontal or anterior. 



C. Front margined; tarsal claws with comb-like teeth. — Melanotus. 

 CC. Front not margined. 



D. Tarsi simple, filiform. — Corymbites. 



DD. Tarsi with the second and third joints lobed beneath.— 

 Asaphes. 



WiREWORMS 



The larvae of click beetles are known as "Wireworms" of which 

 several species are injurious to the roots of cereal crops. Eerhaps the 

 most common are Agriotes mancus, Drasterius elegans, Asaphes de- 



