190 THE CANADIAN ENTOMOLOGIST. 



ments have been repeated the present season, and with results no less 

 favorable than those repotted one year ago. I think it is an established 

 fact that the methods recommended are valuable. They not only seem 

 reliable, but they promise to be the cheapest and most desirable modes 

 that can be made practicable on all occasions. 



As stated last year, the bisulphide of carbon will also destroy the 

 radish maggot ( Anf/io?nyia raphani), but owing to the great number of 

 plants to be treated, the amount of the liquid necessary to do thorough 

 work is large, and so the expense is perhaps too great to warrant its use 

 in case of this insect. The present season I tried to see if we might not 

 make the application in a few places about the bed, at some distance 

 apart, and still effect our purpose to destroy the maggots. The result 

 does not recommend this liquid for the destruction of the radish 

 Anthomyia with the same emphasis that we may safely give in advising its 

 use for the cabbage Anthomyia and the squash ^gerian. This fact led 

 me to cast about for some more desirable agent to be used against the 

 radish fly, and it occurred to me that carbolic acid, which is not only very 

 repellant to insects, but also quite as remarkable in retaining its obnoxious 

 odor for a long time, might be made most serviceable in this warfare. 



I prepared some of this material as follows : To two quarts of soft 

 soap I added two gallons of water. This was then heated to a boiling 

 temperature, when one pint of carbolic acid (in a crude state) was added. 

 This mixture is then set away in a barrel or other vessel, and is ready for 

 use as occasion may require. I mixed one part of this liquid to fifty parts 

 of water, to be used on the radish plants. It was used by three parties 

 in three places. Mr. Lee used it in the College garden, a student — ^Mr. 

 E. Hale — used it on a bed specially prepared, and I used it in my own 

 garden. Mr. Lee sprinkled it on the plants and poured it into a trench 

 made close beside the row of plants. Mr. Hale and myself sprinkled it 

 directly on the plants. Messrs. Lee and Hale made but one application 

 and found that it kept the insects at bay for about two weeks. Even this 

 proved of no little service. I made the application once every week, and 

 the radishes were almost entirely free from the maggots. My bed was 

 seventy or eighty rods from the other beds. But I caught the flies about 

 my garden, and plants near by, not treated, were badly injured by the 

 maggots. Two cautions should be urged j first, sprinkle the plants as 

 soon as they are up, and thereafter every week or ten days ; secondly, the 

 mixture, if sprinkled directly upon the plants, must not be so concentrated 



