ILLUSTRATIONS. 



PLATES. 



Page. 

 Plate II. Work of the western pine-destroying barkbeetle in bark, removed from 



killed tree; also faint marks on surface of wood 18 



III. Work of the western pine-destroying barkbeetle, removed from killed 



tree 18 



TEXT FIGURES. 



Fig. 7. The western pine-destroying barkbeetle (Dendroctonus bremcomis): adult 



male and female and details ~ 18 



8. The western pine-destroying barkbeetle (J9e7Mirocton'Us6re'!7icomis): galleries 



in the inner bark 19 



9. The western pine-destroying barkbeetle {DendroctOTms hrevicomis): larva. 20 



10. The western pine-destroying barkbeetle {Dendroetonus iremcomis) : pupa 22 



11. The western pine-destroying barkbeetle (Dendroetonus hrevieomis): pitch 



tubes on bark of tree 25 



12. The western pine-destroying barkbeetle {Dendroetonus bremeomis): hiber- 



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



VI 



