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inspect tlie work. Accordingly ten entomologists were invited, nine of 

 whom visited tlie territory. We took them over as much of the terri- 

 tory as possible — over the worst ])laces and the best places. I wanted 

 to share the responsibility and I wanted advice. They gave us advice, 

 and a part of their reports has been publish«id in tlie reports of the 

 connnittee. Some of the suggestions liave been adopted; others have 

 not. We were advised to cultivate parasites. The law makes it 

 obligatory upon us to exterminate the insect, so we must kill every 

 caterpillar, whether infested with a parasite or not. and in that way we 

 are exterminating parasites as well. If the State directs to merely 

 hold the insect in check, then is the time to work with parasites. 



In response to a request, Mr. Kirklaud. assistant entomologist to the 

 gypsy moth commission, gave a verbal report on the more recent experi- 

 ments with insecticides conducted by the commission. He saul that no 

 success had been had with insecticides until the arsenate of lead had 

 been devised, and even this, at the rate of 10 pounds to 150 gallons of 

 water, effected the destruction of only about 50 per cent of the larvte. 

 He described his examination of the alimentary canal of the larv?e with 

 a view to determining the probable action of the juices contained in 

 various i^arts of the canal on insecticide substances. He had found the 

 juices strongly alkaline, and of the substances which seemed most likeh* 

 to be acted upon by an alkaline liquid he had considered the cyanides 

 of different metals to be the most promising. The cyanides of lead, 

 antimony, copper, zinc, iron, manganese, mercury, etc., were considered. 

 The cyanides of antimony and copper, on theoretical grounds, seemed to 

 promise best. The cyanide ot* antimony was totally without effect at 

 the rate of 10 pounds to 150 gallons of water. Cyanide of copper was 

 fairly effective, but too expensive for practical employment, 3 pounds to 

 150 gallons being equivalent to 1 pound of Paris green to 150 gallons of 

 water or 3 or 4 pounds of arsenate of lead to 100 gallons. Even where 

 no practical results seem to have been obtained, as in the above series 

 of experiments, he pointed out the value of the negative results; in that 

 the very fact that the merits of these substances have been tested our 

 knowledge of the substances valuable for insecticides is better under- 

 stood and limited. In connection with the various experiments with 

 insecticides he had occasion repeatedly to emphasize the extreme vitality 

 of the gyi)sy moth larva and its immunity from the action of poisons. 



Mr. Riley discussed the gypsy moth (juestion at considerable length. 

 He said he had always been much interested in the gypsy moth work, 

 and referred to the original conference called by the State board of 

 agriculture of Massachusetts, uiving an account of this meeting and 

 of the suggestions nmde by himself and others as to means of control- 

 ling the insect. These suggestions were necessarily based on expe- 

 riences with our well known common insects having somewhat similar 



