CONTENTS. XI 



Detailed information on the species— Continued. Page. 

 No. 14. The eastern spruce beetle— Continued. 



Methods of control T T ....... , 123 



Basis of information ....-..-- 125 



Bibliography 125 



No. 15. The Engelmann spruce beetle (Dendroctonus engelmanni Hopk.). . 126 



Seasonal history. 126 



Overwintering stages 126 



Activity of overwintered broods 127 



Economic features 127 



Methods of control 131 



Basis of information 131 



Bibliography 132 



No. 16. The Alaska spruce beetle (Dendroctonus borealis Hopk.) 132 



Bibliography , 132 



No. 17. The Sitka spruce beetle (Dendroctonus obesus Mann.) 132 



Seasonal history 133 



Overwintering stages 133 



Activity of overwintered broods. 133 



Generation . . 134 



Habits 134 



Economic features 135 



Methods of control 135 



Basis of information 136 



Bibliography 136 



No. 18. The redwinged pine beetle (Dendroctonus rufipennis Kirby) 136 



Seasonal history 137 



Habits 137 



Basis of information 138 



Bibliography 138 



No. 19. The lodgepole pine beetle (Dendroctonus murrayanx Hopk.) 138 



Habits 138 



Basis of information 139 



Bibliography 139 



No. 20. The Allegheny spruce beetle (Dendroctonus punctatus Lee.) 139 



Basis of information 140 



Bibliography 141 



No. 21. The European spruce beetle (Dendroctonus micans Kug.) 141 



Habits and seasonal history 141 



Economic features 142 



Methods of control 142 



Information from paper on the genus Dendroctonus, by Dr. G. Severin 



(1908) 142 



Specimens 146 



Bibliography 146 



No. 22. The black turpentine beetle (Dendroctonus terebrans Oliv.) 146 



Seasonal history 147 



Northern section 147 



Overwintering stages 147 



Activity of overwintered broods 147 



Generation 148 



Southern section 148 



Habits. 149 



