Tech. Series 1 7, Part 1, Bureau of Entomology, U. S. Dept. of Agriculture. 



Plate IV. 



Dendroctonus Adults. 



Fig. 8.— I). <ipproximatus. Yig.'i.—D. monticolci'. Fig. 10.— J >. ponder osn'. Fig. 11.— D.jcffreiji. 



(Original.) 



