328 ANNUAL REPORT OF NEW-YORE 



APPLE. TRUNK. 



diameter, whilst those of this insect measure 0.06. A specimen 

 of the wood sent me, shows a perforation made by this larger 

 insect, running in a straight line through the bark and into the 

 wood three-fourths of an inch, with three lateral galleries of the 

 same size branching oif from this at right angles upon one side, 

 and one upon the opposite side, these galleries being excavated 

 up and down parallel with the grain of the wood. 



It thus appears that the pear blight beetle, instead of being 

 limited to the twigs in its operations, as has heretofore been sup- 

 posed, attacks the trunk of the tree also. And it is therefore 

 evident that there are tw^o generations of this insect each year. 

 The new shoots at the ends of the limbs are not sufficiently grown 

 to accommodate the earliest brood, and they are therefore nurtur- 

 ed in the trunk of the tree. When these reach maturity, the 

 newly grown twigs offer them a more dainty repast, and they 

 accordingly resort to them, blighting and destroying them in the 

 manner hereafter stated in the account of this insect. No. 56. 



It was formerly supposed that the bark beetles only infested 

 trees which were already dying or dead. But more recent obser- 

 vations have shown that sound healthy trees are attacked and 

 killed by them. And these observations are fully confirmed by 

 Mr. Smith, w^ho states that it is young thrifty apple trees, that 

 made a most vigorous growth last summer, which have been 

 killed this past spring by these insects. 



Worms CQnsu7ning the wood of old and hollow trees, hastening their decay. 



The larvse of quite a number of beetles feed upon the old and 

 decaying wood of almost all our trees, showing little preference 

 for one tree over another. Those only which from their very 

 large size will be liable to attract notice when found as they fre- 

 quently are in the interior of aged apple trees, may here be speci- 

 fied, although they are equally common in oaks, willows, &c. 



6. Horn-bug, Lucanus Capreolus, Linnaeus. (Coleoptera. Lucanidas.) 



Large thick nearly cylindrical white worms, with the hind part 

 of their bodies curved downwards and forwards, their heads and 

 six legs tawny reddish, the mouth darker. In the loose dirt 

 which accumulates in the hollow of the tree, forming large hard 



