204 



COLEOPTERA— BEETLES 



ings between the bark and the wood. They are a great 

 economic pest in forests. The pine forests of Virginia, 

 Georgia, etc., and tlie Black Hills have been greatly injured. 



Fig. 158. — Dendroctonus valen^: work in bark at base of stump: a. en- 

 trance and pitch tube; b, egg gallery; c, boring dust and resin; d, pupal 

 cell; e, pupa; /, larvae at work feeding on inner living bark; £/, exit burrows; 

 h, resulting old scar or basal wound, often referred to as basal fire wound; 

 i, inner bark with outer corky bark removed. (A. D. Hopkins, Bur. Ent.. 

 U. S. Dept. Ag.) 



