April, '10] IIERTZOG : "CIGAKETTE BEETLE' 199 



has taken steps to gather more definite statistics as to the extent of 

 damage and distribution. In buildings heated during the winter, 

 and in Marm climates, it may breed the entire year. In a cold build- 

 ing they are inactive. In the latitude of Pennsylvania there are two 

 broods running into each other, but the adult beetles are most abun- 

 dant during the middle of June and again the middle of September. 



The real proposition and question is how to get rid of it. A small 

 quantity of tobacco may be readily and satisfactorily fumigated. But 

 a large warehouse full is a different proposition. Especially so when 

 the house is not of a very tight nature or when the cases are stored 

 four or five rows deep and three or .four layers on top of each other. 

 Under such conditions it is impossible to fumigate successfully, since 

 the gas could not readily reach the interior and lowermost cases. A 

 packer will ask, will not the gas deteriorate the tobacco by bleaching 

 it or imparting an odor? Will fumigation really kill the insects? 

 During my summer's work, it was necessary in each instance to try a 

 few cases in a sample room to show the merits of the work. In each 

 instance the owners were pleased. As to the success of fumigation 

 with hydrocyanic acid gas for the cigarette beetle, entomologists are 

 somewhat divided, yet most see in it the most practicable remedy. 

 This paper is based on the result of its use. It must be remembered 

 that tobacco is one of the most difficult products to fumigate because 

 the leaves pressed tightly against each other and the whole mass 

 packed and pressed into the case forms an almost impenetrable mass. 

 Fortunately most of the insects are on the outer portions of the case 

 and especially at the butt end of the tied hands or bundles. It is- 

 there that they can gain the best entrance both into the case and into 

 the tobacco. ]Most of the injury is done from the butt end in for 

 about ten inches. The interior of the case, where the leaves are the 

 most valuable, is usually free from insects. They eat inwards along 

 and even through the ribs, piercing the leafy part at random. The 

 gas may follow them in their channels. However, in order to do so a 

 large amount of gas is necessary and a long time is required for it 

 to penetrate. 



Hydrocyanic acid gas gave most excellent results this summer. Yet 

 it was by no means perfect. The ordinary directions and precautions 

 for fumigating were followed. The formula per 1,000 cu. ft. of room 

 space was 12 ounces of potassium cyanide, 20 ounces of sulphuric 

 acid (liquid measure) and 40 ounces of water. The building is in 

 very good condition, being as nearly gas tight as is to be expected. 

 The gas was allowed to act over twenty-four hours. There was a two- 

 foot aisle between the cases, but they were three cases high. The 



