PEACH INSECTS 



283 



wood, but gradually diverge as they advance. In 25 or 30 days 

 the full-grown grubs transform to pupte in the enlarged ends 

 of the burrows near the outer surface of the bark. From 4 to 

 6 days are spent in the pupal stage, but as a rule the beetles do 

 not emerge until a week or two later. In northern Ohio there 

 are two generations a year, the beetles appearing in greatest 

 numbers in March and early April, in July and again in October, 

 when they go into hibernation. The broods overlap, so that 

 after July all stages are present under the bark until cold weather. 



Fig. 245. 



Burrows of the peach bark-beetle ; (e. n.) egg nitrh. 

 after Swaine. 



Redrawn 



The beetles may be distinguished from the preceding species 

 by the following points : the club of the antenna is lamellate ; 

 when viewed from the side the venter of the abdomen appears 

 nearly straight, not turned abruptly upward and the pronotum 

 is bent strongly downward, so that the head is scarcely visil)le 

 from above (Fig. 244). 



Treatment. 



The measures suggested against the fruit-tree bark-beetle 

 are also applicable to the present species. From experiments 

 conducted in Ohio it is recommended that, in order to keep out 

 the greatest number of beetles, the whitewash should be ap- 



