ILLUSTRATIONS. [X 



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Fig, 18. Dendroctonus valens: Mesothorax, ventral aspect 2 



19. Dendroctonus valens: Mesotergum and mesopleurum 28 



20. Dendroctonus valens: Metatergum and metapleurum 31 



21. Dendroctonus valens: Metatergum, inner aspect 33 



22. Dendroctonus valens: Abdominal tergites 35 



23. Dendroctonus valens: Male, abdominal tergites 7 and 8 36 



24. Dendroctonus valens: Female, abdominal tergites 7 and 8 37 



25. Dendroctonus valens: Abdominal sternites, ventral and lateral 



aspects 38 



26. Dendroctonus valens: Tibia, tarsus, articulation, etc 40 



27. Dendroctonus: Left tibiae, dorsal and ventral aspects 41 



28. Dendroctonus: Left tiliite, dorsal and ventral aspects 42 



29. Dendroctonus: Left tibiae, dorsal and ventral aspects 43 



30. Dendroctonus valens: Diagram of basal area of hind wing 44 



31. Dendroctonus valens: Right elytron, ventral aspect 45 



32. Dendroctonus valens: Basal process of right elytron 46 



33. Dendroctonus valens: Declivital section of elytra 46 



34. Dendroctonus valens: Diagram of elytron, showing striae, interspaces, 



and tracheae 47 



35. Dendroctonus valens: Digesti^'e organs of adult 52 



36. Dendroctonus valens: Fore intestine, showing details 53 



37. Dendroctonus valens: Pupa, dorsal, lateral, and ventral aspects 54 



38. Dendroctonus valens: Pupa, lateral and anal aspects 55 



39. Dendroctonus valens: Larva, dorsal, lateral, and ventral aspects 58 



40. Dendroctonus valens: Head of larva 59 



41. Dendroctonus valens: Mouth parts of larva 60 



42. Dendroctonus valens: Mandibles of larva 63 



43. Dendroctonus valens: Digestive organs of larva 65 



44. Dendroctomts brevicomis: Egg galleries 82 



45. Dendroctonus brevicomis: Bark showing pupal cells, exit burrows, 



and pitch tubes 83 



46. Dendroctonus brevicomis: Distribution map 84 



47. Dendroctonus barberi: Egg galleries 86 



48. Dendroctonus barberi: Distribution map 87 



49. Dendroctomts convexifrons : Egg galleries and larval mines 89 



50. Dendroctonus convexifrons: Distribution map 90 



51. Dendroctonus frontalis : Egg galleries and larval mines 91 



52. Dendroctonus frontalis: Termination of egg galleries 92 



53. Dendroctonus frontalis : Beginning of egg galleries 92 



54. Dendroctonus frontalis : Bark showing pitch tubes, etc 92 



55. Dendroctonus frontalis: Old egg galleries in living trees 93 



56. Dendroctonus frontalis : Egg gallery in living tree, the resulting 



wound in process of healing 93 



57. Dendroctonus frontalis : Distribution map 94 



58. Dendroctonus arizonicus: Distribution map 97 



59. Dendroctonus mexicanus: Section of egg galleries 98 



60. Dendroctonus mexicanus: Distribution map 99 



61. Dendroctonus parallelocollis : Section of egg gallery 100 



62. Dendroctonus parallelocollis: Distribution map 101 



63. Dendroctonus approximatus: Single egg gallery 102 



64. Dendroctonus approximatus: Egg galleries 103 



65. Dendroctonus approximatus: Distribution map 104 



66. Dendroctonus monticolse: Egg galleries and larval mines in bark 107 



