200 INDIRECT INJURIES CAUSED BY INSECTS. 



is mentioned by Mr. Forsyth as very injurious to this 

 tree '^. 



But of all our fruits none is so useful and important 

 as the apple, and none suffers more from insects, which 

 according to Mr. Knight'' are a more frequent cause of 

 the crops failing- than frost. The figure-of-eight moth 

 (Bombt/x cceruleocephala, F.) Linne denominates the 

 pest of Pomona and the destroyer of the blossoms of 

 the apple, pear, and cherry. — He also mentions an- 

 other ( Tinea Corticella, F.) as inhabiting apple-bearing 

 trees under the bark. — And Reaumur has given us the 

 history of a species common in this country, and pro- 

 ducing the same effect, often to the destruction of the 

 crop, the caterpillar of which feeds in the centre of our 

 apples, thus occasioning them to fall*^. Even the young- 

 grafts, I am informed by an intelligent friend*^, are fre- 

 quently destroyed, sometimes many hundreds in one 

 night, in the nurseries about London, by Curculio VaS' 

 tutor ^ Marsh, (C. picipes, F.) one of the short-snouted 

 weevils — and the foundation of canker in full grown 

 trees is often laid by the larvse oiTortrix Wceberana^. 

 — But the greatest enemy of this tree, and which has 

 been known in this country only since the year 1787, is 

 the apple-aphis, called by some the Coccus, and by 

 others the American blight. This is a minute insect, 

 covered with a long cotton-like wool transpiring from 

 the pores of its body, which takes its station in the 

 chinks and rugosities of the bark, where it increases 

 abundantly, and by constantly drawing off the sap causes 



* On Fruit Trees, 271, " On the Jpple and Pear, 45, 

 " Reaum. ii. 499. " Mr. Scales. 



* See Ohservations on this Insecl iu the 2d volume of the IIorticuUura,l 

 Society's Transactions p 25. By W. Spence. 



