61 



Selandria rubi. The Raspberry Slug. 



This insect appeared upon the raspberry plants this year at several 

 points in the Northern and Western portions of the State, doing con- 

 siderable injury. I also received letters' from Iowa informing me of 

 their appearance in that State, and complaining that they had almost 

 entirely denuded the plants of their foliage, in some cases. As re- 

 quested by the writers, I replied through one of the agricultural 

 papers, (The Western Farm Journal,) giving the name of the insect 

 and the remedies recommended. 



The worms, up to their last moult, are smooth and green ; the head 

 black or marked with a central black spot ; they have twenty-two 

 feet, those on the middle segments being very small. After their last 

 moult, they have spines on the body. 



The perfect insect is a small four-winged fly belonging to the order 

 Hymenoptera and family Tenthredinidw, having somewhat the appear- 

 ance of a short, thick-bodied wasp. It is of a dusky color. 



This species has heretofore appeared at various points in Illinois 

 and Iowa in considerable numbers, but it does not appear to have re- 

 mained long, which indicates that it is subject to some destructive 

 parasite, and that it will not continue year after year in great num- 

 bers at any one place. 



It belongs to that group of insects whose larva? have received the 

 name of " Slugs." It is probable, therefore, that a remedy applicable 

 to a closely allied species will be equally beneficial if applied to this. 

 I call attention, therefore, to the use of white hellebore, which Mr. 

 Walsh believed to be a specific for the gooseberry slug. He recom- 

 mended applying the powder with a cup attached to a rod, and hav- 

 ing a piece of thin muslin tied over the mouth or top ; taking care to 

 stand to the windward during the operation, as it causes violent 

 sneezing if taken into the nostrils. 



Mr. Saunders, of London, Ontario, Canada, experimenting with the 

 imported gooseberry saw-fly (Nematus ventricosus) found that if the 

 hellebore was mixed with water, an ounce and a half to the pail of 

 water, it was much more effectual than if applied in powder. He 

 tried the carbolate of lime, which has been so strongly recommended 

 by some for these and similar slugs, but the result was far from satis- 

 factory. It is possible that finely powdered lime sprinkled on the 

 raspberry slugs when quite young, especially if this is done very early 

 in the morning while they are at work will be sufficient. As a usual 

 tiling, I believe they commence feeding before day-light. 



