19S INDIRECT INJURIES CAl'SED BY INSECTS. 



the cause of any very material injury. But in North 

 America a second species nearly related to it, known there 

 by the name of the s/i^-tcorm, has become prevalent to 

 such a degree as to threaten the destruction not only of 

 the cherry, bat also of the pear, quince, and plum. In 

 1 797 they were so numerous that the smaller trees were 

 covered by them ; and a breeze of air passing through 

 those on which they abounded became charged with a 

 disagreeable and sickening odour. Twenty or 

 thirty were to be seen on a single leaf; and many trees, 

 being quite stripped, were obliged to put forth fresh 

 foliage, thus anticipating the supply of the succeeding 

 year and cutting off the prospect of fruit *. In some 

 parts of Germany the cherry-tree has an enemy equally 

 injurious. A splendid beetle of the weevil tribe (Ryn- 

 chites Bacchus) bores with its rostrum through the half- 

 grown fruit into the soft stone, and there deposits an 

 egg. The grub produced from it feeds upon the kernel, 

 and, when about to become a pupa, gnaws its way through 

 the cherry, and sometimes not one in a thousand escapes b . 

 This insect is fortunately rare with us, and has usually 

 been found upon the black-thorn. The cherry-fly also 

 ( Tepkritis Cerasi) provides a habitation for its maggot 

 in the same fruit, which it invariably spoils c . 



The different varieties of the plum are every year 



animal inhabiting the sallow. Probably, confounding the two species, 

 he described the imago from the insect of the former, and the larva 

 (if he did not copy from Reaumur or Linne; from that of die latter. 

 was correct in regarding Reaumur's three insects as distinct 

 though be appears to be mistaken in referring to him under 

 as the saw-fly of the currant and gooseberry is not wholly 

 yellow. 



1 Peck's Xat. BuL of fa Slug-worm, 9. 



* TmtJOdiicr&ytrag.SS. e Reaura.il 47 



