INSECTS INJURIOUS TO THE APPLE. 



Explanation of flrjures — a, the eggs; h, the eggs magnified; c, the Caakcr-worm or larva; d, the 

 «<»coon; &, the pupa; /, the male moth; g, the female. 



THE CANKER-WORM, 



( Aniiopteryx vernaia, Peck. ) 



Order of LEPIDOPTERA. Family of Geomitridje. 



Harris's Treatise, (Ed. 1862) page 461; Riley's ?d Rep., p. 94. 



Amongst the many kinds of insects which are injurious to mankind 

 a comparatively small number have been so extensively destructive, 

 and have become so generally known, that they might be appropri- 

 ately called, by way of distinction, first-class noxious insects. 



In order to be entitled to this bad preeminence, an insect must pos- 

 sess a certain number and degree of obnoxious qualities. In the first 

 place it must depredate upon some one of ;*he mere valuable produc- 

 tions of the soil upon which mankind depend for subsistence and 

 profit. In the next place it must be sufficiently numerous to attract 

 general notice, and to demand the most prompt and energetic measures 

 for its suppression. And, thirdly, it must extend over a sufficient area 

 of country to make itself felt, not only upon individual welfare, but 

 also upon the commercial interests of the country. 



Tried by these tests but very few of the many insects treated of in 

 our Reports and Treatises upon noxious insects, can be admitted into 

 this primary class ; and of these some would enter without question, 

 whilst the claim of others would be regarded as debatable. Amongst 



