THE GENUS DENDROCTONUS. 



133 



Host trees. — Picea engelmanni and P. canadensis. 



Identified specimens. — Le Conte collection, 2 specimens; Horn, 2; 

 Dietz, 1 (Utah); U.S.N.M. (H. & S.), 4; Wickliam, 4; Cockerell, 7; 

 Webb, 25; Hopk. U. S., more than 200 specimens, including all 

 stages and work. 



Fig. 82. — Dendroctonus engelmanni: Distribution map. (Original.) 



Bibliography and Synonymy. 



Dendroctonus rufipennis (not of Kirby) Le Conte, 1876, p. 385, revision (?). Le 



Conte, 1878; p. 469 (in part) (in collection 1900-1907, under D. rufipennis). 



Packard, 1887, pp. 177-243 (in part). Packard, 1890, p. 721 (in part), p. 722 (in 



part), quotes Le Conte. Dietz, 1890, p. 30, Colorado, Utah. Wickham, 1902, p. 



309, list, localities. 

 Dendroctonus dietzi Hopkins, 1902a, manuscript name only for variation (Utah). 

 Dendroctonus californicus Hopkins, 1902a, p. 3, manuscript name only, locality. 

 Dendroctonus wickhami Hopkins, 1902a, p. 3, manuscript name only. 

 Dendroctonus 2nceaperd.a (not of Hopkins) Wickham, 1902, p. 310, in list, locality, 



host, reference to synonymy. Hopkins, 1906a, pp. 4, 5, old work on Pike's Peak. 

 Dendroctonus piceaperda var. engelmanni (Hopk.) Fall, 1907, p. 218, manuscript name, 



list, localities. 

 Dendroctonus piceaperda (not of Hopkins) var. Fall, 1907, p. 218, list, Cloudcroft, 



N. Mex. 

 The Engelmann spruce beetle. Hopkins, 1908, pp. 161-162, depredations. 



16. Dendroctonus borealis n. sp. 



(PI. V, fig. 16.) 



Adult. — Type of species, female: Length 6 mm., nearly black. 

 Head with front convex, with faint anterior and posterior impressions 

 and faint anterior line; elytral declivity with striae not deeply im- 



