16 BULLETIN NO. 4, DIVISION OF ENTOMOLOGY. 



Copperas. — This poison is recommended as a certain care by Senator 

 Einsen, and lie shows his faith in it by using it himself and recommend- 

 ing it to all others; but all experiments so far tried have failed to de- 

 monstrate its value as an insecticide — this insect of course in view. Dr. 

 Brakeley has given it a thorough trial, and deems it'valueless, and oth- 

 ers give similar testimony. Decisive of the matter is the testimony of 

 Mr. Einsen's secretary and manager. This gentleman informed me that 

 he had transplanted some vines in a large jar, had placed therein a num- 

 ber of larva? and so thoroughly soaked the whole with a solution of cop- 

 peras that the leaves turned black ; in a few days the larvae had devoured 

 everything, and were still perfectly healthy and ravenous. 



Tobacco. — This is the favorite Cape Cod reined}", and the testimony 

 gathered there is all in its favor. The tobacco is steeped in boiling 

 water in the proportion of 1J pounds to a gallon, and sprinkled on the 

 vines, a gallon to a rod. The testimony of all who have so used it is 

 to the effect that it kills the larva? wherever it reaches them, but they find 

 it somewhat difficult to reach them. There is a gentleman in Dennis^ 

 on the Cape, who makes somewhat of a business of preparing the decoc- 

 tion, and he claims that it is infallible. I was unfortunate in reaching- 

 Dennis at camp-meeting time, and did not succeed in finding this gen- 

 tleman. Eefuse tobacco of all sorts is used. 



Paris green. — This poison has been used in a few instances that I 

 kiK>w of, and probably in a quiet way to a considerable extent on the 

 Cape. In New Jersey its use has been confined to a few, but wherever 

 it has been used it has been a decided success. I have seen bogs on 

 which it was used, parts only having been treated with it, and the dif- 

 ference in the appearance of the vines was striking : where it had been 

 used the vines were green and flourishing, while elsewhere they were 

 dry, unsightly, spun up and defoliated. It has been used stirred in 

 water, a large tablespoonful to a pail of water, sprinkled on with a 

 broom, and mixed with plaster, or rye flour. The latter is the prefer- 

 able way. On Cape Cod the solution is preferred, in New Jersey the 

 dry mixture is more favored. One grower mixed 3 pounds Paris green 

 with 200 pounds cheap rye flour and scattered it broadcast while the dew 

 was on the vines; it formed a slight paste and adhered everywhere; 

 soon after not a larva was found on the part so treated. The advantage 

 of this poison over all others is that it does not lose by exposure to the 

 air as do all those previously mentioned: its disadvantage is that, ap.- 

 plied when the berries have become fully formed, it sticks to them so 

 closely that the gentleman referred to found the berries picked off the 

 poisoned sections all more or less coated with the poisoned paste, which 

 had dried on so closely that a heavy rain had not washed it off. Yet this 

 poison may be safely applied early in the season to combat the first 

 brood, before the berries have formed. 



Pyrethrum, or Persian Insect Powder. — With this I have made a num- 

 ber of experiments : first as to its killing power. A few 



