ILLUSTRATIONS, 



PLATES. 



Page. 

 Plate IT. Work of the western pine-destroying harkheetle in hark, removed from 



killed tree; also faint marks on surface of wood 18 



III. Work of the western pine-destroying barki)eetle, removed from killed 



tree 18 



TEXT FIGURES. 



Fig. 7. The western pine-destroying harkheetle (Deiulrocfoiiiis ]»rvico7rii)^): adult 



male and female and details 18 



8. The western pine-destroying harkheetle {Dendroctorni.sbrevicomis): galleries 



in the inner hark 19 



9. The westein pine-destroying harkheetle {Deridroctonus brevicomis) : larva. 20 



10. The western pine-destroying harkheetle {Dendroctomtshreincomis): pupa 22 



11. The western pine-destroying harkheetle {Dendrocionus hrevicomis) : pitch 



tuhes on hark of tree 25 



12. Thf western pine-destroying l)arkl)eetle {Dendroctonus hirricomis): hiher- 



nating or transformation cell, exit hurrow, exit holes, pitch tubes 26 



VI 



