35 



other products become infested. He had recently performed one of 

 the largest experiments ever undertaken in the use of hydrocyanic- 

 acid gas, in a five-story brick mill in Canada. Over 150 pounds of 

 potassium cyanide was discharged in the mill, and the results were 

 very gratifying. It practically eliminated the flour moth from the 

 mill. ^' 



Mr. Fletcher said he did not think enough care could be taken in 

 giving instructions when recommending hydroc^'^anic-acid gas for gen- 

 eral use, especially in this stage of introducing it, as a fatal case or 

 two would put an end to its use entirely. Several striking instances 

 had lately been mentioned which show the intensely poisonous nature 

 of this gas. Much more care, instead of less, than has been exercised 

 in the past is necessary. With regard to the use of bisulphide of car- 

 bon, he certainly was not satisfied with its use in mills, and had not 

 got the results promised for it. He was very sorry Mr. Marlatt was 

 not present at the meeting, as his laisser-faire policy had given him a 

 lot of trouble with the people he had to deal with, and he was of the 

 opinion that some others of the Association might have liked to discuss 

 that matter somewhat. 



Mr. Sanderson suggested the use, in cases where only a small amount 

 of the gas is required, of gelatine capsules, which require about one 

 minute to be eaten through by the acid, thus giving time to get the 

 box closed. 



Mr. Webster stated that his fumigating houses in Ohio are covered 

 carefully and made perfectly air-tight by the use of layers of building- 

 paper, but if the ordinary nurseryman makes his own fumigating 

 house he would not make it any more air-tight than a hencoop. He 

 had tried almost every way of introducing the cyanide. ])ut the man 

 who did the work iuA'arialjl}^ complained of severe headache, until he 

 devised a method of combining the mixtures under the floors. 



Mr. Lounsbury suggested that a simple way w^as to have a small 

 lead tube leading from the outside of the house, the vessel containing 

 the cyanide being placed under the tube, the door closed and locked, 

 and the water and acid freshly mixed being poured in through the 

 little funnel or tube and the aperture closed. 



The next paper was entitled: 



OBSERVATIONS ON DIABROTICA 12-PUNCTATA OLIV. 



By A. L. QuAiNTANCE, Experhneiit, (lu. 



In the Southern States particularly this insect is a corn pest of con- 

 siderable importance. Injury to the corn plant is confined almost 

 entirely to the work of the larva? on the underground portions of the 

 plant, as the roots and stem below the soil. Injury results to corn 



