INSECTS AFFECTIXr, PAKK AND WdODLANI) TREES 



3S7 



Description. The beetle varies from a lij;ht brown to a black. It is 

 quite small, Ijeiii^' about ? yj inch lon-^r and with a rather stout form. The 

 head is thickly and finely punctureil and nearly concealed by the overhan<T- 

 ini^ prothorax. The mouth parts are tii)[)eil with black and the concolorous, 

 coarsely i^^ranulated eyes are di\ided, the two [jortions beiuL^ connectetl by 

 a smooth strip of chitin. The |)rothorax is much narrowetl in front, thickly 

 and finely jnuictured and the win;^ covers or elytra are rouijh, finely 

 punctured and almost striate. The structure of the antennae is shown on 

 platt' 67, fiL,^ure 8, and that of the tibia in figure H~,c7 . 



The white pupa is about the same size as the beetle, rather stout 

 antl with a taperin<,r abtlomen terminated by a pair of lleshy spinelike 

 processes. 



The brown headed, white j^rubs or larvae are about '^ inch lont^ 

 when full Li'rown. The mouth parts and atljacent sutures are a tlark brown 

 and the boily is usually somewhat curved. 



Life history. I he life history ot this borer in West \'irginia has been 



given by I)r Hopkins as follows: 



The adults emerge in May or June and are attracted to stumps, trunks 

 and tops of recently fallen trees ancl those that are weakened by the attack 

 of insects, such as the destructive ]jine bark beetle, Dendroctonus 

 frontalis Zimin., or diseases of any kinds. The beetles commence to 

 excavate entrance galleries through the outer bark, and their jirescnce is 

 indicated by the fine brownish borings in the crevices of the bark. This 

 entrance is extended to the outer surface of the inner soft bark where the 



central chamber is excavated. In the meantime, the 

 ^i^^T'~——~~'^_^^^\ f<-'"'''ilc, which appears to do the greater part of the 

 ''- ' ;-:=a^^™u work, is joined by a male who stations himself in the 



outer gallery to keep out enemies and objectionable 

 visitors and to render assistance in expelling the bor- 

 ings. The female excavates a galler)- from one edge 

 of the central chamber through the inner bark of the 

 wood and then in the inner layer of the bark, usually 

 at right angles to the bark fibers, and for a distance 

 Fig. 86 Poivcrnphus rufi- of onc or two inchcs. .Small notches are made alontr 



pcnnis: early pnllcrics and cgc ^i • i r ..1 1 1 11 • i r i • i i^ 



notches (.-.uthor-s illustration) thc sidcs ol the brood gallery, m each of which pearly 



white eggs are deposited. One to three other females 

 are admitted to this central chamber by the male and from it extend similar 



