528 HYMENOPTKRA. 



application, may be found in the " Boston Courier " for 

 the 25th of June, 1841, and also in most of our agricultural 

 and horticultural journals of the same time. The utility of 

 this mixture has already been repeatedly mentioned in this 

 treatise, and it may be applied in other cases with advantage. 

 Mr. Haggerston finds that it effectually destroys many kinds 

 of insects ; and he particularly mentions plant-lice, red spi- 

 ders, canker-worms, and a little jumping insect which has 

 lately been found quite as hurtful to rose-bushes as the slugs 

 or young of the saw-fly. The little insect alluded to has 

 been mistaken for a Thrips or vine-fretter ; it is, however a 

 leaf-hopper, or species of Tettigonia, and is described in a 

 former part of this treatise. 



According to the plan to which I have found it necessary 

 to limit this work, only one more species of saw-fly remains 

 to be described. Of the habits and transformations of this 

 insect the late Professor Peck has given us an admirable 

 account, under the title of a " Natural History of the Slug- 

 Worm," which was printed in Boston, in the year 1799, by 

 order of the Massachusetts Agricultural Society, and ob- 

 tained the Society's premium of fifty dollars and a gold 

 medal. As my own observations on this insect agree per- 

 fectly with those of Professor Peck, in the following remarks 

 I have merely abridged and condensed his " Xatural History 

 of the Slug- Worm," a work now out of print, and rarely 

 to be met with. It will be proper to premise that Professor 

 Peck was inclined to believe this slug-fly to be a variety of 

 the Tenthredo Oerasi of LinnaBus, an insect found more com- 

 monly on the pear-tree in Europe than on the cherry, al- 

 though it has a specific name derived from the latter tree. 



Most naturalists now reject the name given by Linnasus 

 to the slimy grub of the pear-tree, because it is not strictlv 

 correct, and substitute a specific name imposed upon it by 

 Fabricius. The European insect, therefore, is now called 

 Selandria (^Blennocampa) ^thiops ; and a good account of 

 it, by Mr. Westwood, may be found in the thirteenth volume 



