DUTCH ELM DISEASE 



13 



Figure 6. The Work of the Carrier Beetles. 



Upper Left: Characteristic egg gallery of Scolylus multistriatus beneath the bark of a 



dead elm tree. Actual size. ,..,.. j ,. .- ;„„ „f v,„ ifv,„ 



Upper Right: Bark punctures of young Scolytus multistriatus adults on twigs or neaitny 



Lower Left: Bark punctures of young Hylurgopinus rufipes adults in the trunk of a 

 healthy elm tree. Actual size. . . ,, ,, . „,, „*-_ 



Lower Rkjht: Characteristic egg gallery of Hylurgopinus rufipes beneath the barK 01 a 

 dead elm tree. Actual size. 



