382 INSECTS INJURIOUS TO VEGETATION. 



now seem to be gradually extending in all-directions, and an ef- 

 fectual method for preserving our roses from their attacks has 

 become very desirable to all persons who set any value on this 

 beautiful ornament of our gardens and shrubberies. Showering 

 or syringing the bushes with a liquor, made by mixing with water 

 the juice expressed from tobacco by tobacconists, has been rec- 

 ommended ; but some caution is necessary in making this mix- 

 ture of a proper strength, for if too strong ii is injurious to plants; 

 and the experiment does not seem, as yet, to have been conduct- 

 ed with sufficient care to insure safety and success. Dusting lime 

 over the plants when wet with dew has been tried, and found of 

 some use ; but this and all other remedies will probably yield in 

 efficacy to Mr. Haggerston's mixture of whale-oil soap and wa- 

 ter, in the proportion of two pounds of the soap to fifteen gallons 

 of water. Particular directions, drawn up by Mr. Haggerston 

 himself, for the preparation and use of this simple and cheap ap- 

 plication, may be found in the "Boston Courier," for the twenty- 

 fifth of June, 1841, and also in most of our agricultural and hor- 

 ticultural 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 of various kinds, red spiders, 

 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 

 species of Thrips or vine-fretter ; it is, however, a leaf-hopper, 

 or species of Tettigonia, much smaller than the leaf-hopper of 

 the grape-vine (Tettigonia Vitis), described in a former part of 

 this essay,* and, like the leaf-hopper of the- bean, entirely of a 

 pale green color. 



According to the plan to which I have found it necessary to 

 limit this essay, 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 



* Page 184. 



