LLUSTRATIONS. 



PLATES. 



Page. 



Plate I . Work of the locust borer ( Cyllene robiniae) 2 



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. 1. The locust borer (Cyllene robiniae) : Larva 2 



2. The locust borer: Eggs, larvae from hibernation cells 3 



3. The locust borer: Male and female beetles 4 



4. The locust borer: Pupa ' 5 



5. The locust borer: Hibernation or larval cells 10 



6. The locust borer: Reproductive organs of female 11 



7. The western pine-destroying barkbeetle (Dendroctonus brevicomis) : 



Adult male and female, and details 18 



8. The western pine-destroying barkbeetle: Galleries in the inner bark. . 19 



9. The western pine-destroying barkbeetle: Larva 20 



10. The western pine-destroying barkbeetle: Pupa ' 22 



11. The western pine-destroying barkbeetle: Pitch tubes on bark of tree. . 25 



12. The western pine-destroying barkbeetle: Hibernating or transforma- 



tion cell, exit burrow, exit holes, pitch tubes 26 



13. The effect of the storm of April 24, 1908 44 



14. The southern pine saywer (Monohammus titillator) : Male and female. . . 46 



15. The southern pine sawyer: Egg and details 47 



16. The southern pine sawyer: Larva and details 47 



17. The southern pine sawyer: Pupa 48 



18. The southern pine sawyer: Egg pit and eggs in position 51 



19. The southern pine sawyer: Gallery and details 52 



20. The southern pine sawyer: Cross section of pupal cell 52 



21. The southern pine sawyer: Work of larvae in bark 53 



22. The southern pine sawyer: Emergence holes of young adults 54 



23. Bracon (Melanobracori) webbi: Dorsum of second abdominal segment ... 54 



24. Bracon (Melanobracon) webbi: First four antennal joints 54 



VII 



