FIG. 3^. <?, The bronze birch borer beetle, natural size in lower coi ner : />, t lie grub 

 or borer, natural size above. 



FIG. 36. a, Portion of trunk of white birch with bark removed to shoio how tlie burrows of 

 the borer sometimes zigzag across eacJi oilier ; b, shows a burrow extending through the 

 wnod : r, hibernating and transforming chambers in tlie wood a short distance beneath the 



bark. All figures reduced slightly. 



