THE CANADIAN ENTOMOLOGIST. 119 



CORRESPONDENCE. 



USE OF CHLOROFORM IN COLLECTING. 



Dear Sir, — In the article of Henry S. Saunders, on Collecting at the 

 Electric Light (Can. Ent., Feb., 1S87), he gives his experience in the use 

 of cyanide of potassium and chloroform as follows : " Cyanide of potas- 

 sium I found the best poison ; a few drops of chloroform on cotton would 

 quiet them more quickly, but was more troublesome, the chloroform 

 having to be frequently renewed, occasionally as often as four or five 

 times during the same evening, and sometimes even then the moths 

 would be found alive the next morning " 



I should like to explain my method of collecting with chloroform. I 

 have found it better than any other, whether at the electric light or in 

 the field : 



Take a glass fruit jar, one in which the lid screws down upon a 

 rubber cushion or packing. Put a bunch of cotton in the bottom, 

 retaining it in its place by pressing down upon it a circular piece of 

 pasteboard, made to fit tightly in the jar, except that two or three 

 notches should be left in the edge for the chloroform to run through to 

 the cotton. Saturate the cotton with chloroform and screw the lid down 

 tight. The bottle is now ready for use, and it will be found that an 

 insect dropped into it will be suffocated almost instantly by the fumes of 

 chloroform that completely fill the bottle. A feeble flutter for a second, 

 a kick or two, and all is over. As soon as the insect is dropped into the 

 bottle, screw the lid down again, and as it fits air tight, the chloroform 

 will not evaporate too rapidly. Less than a teaspoonful will last for a 

 whole evening's work. If on retiring from the work the chloroform seems 

 nearly exhausted, it would be well to pour in a few drops more, and then 

 close the lid for the night. If these precautions are taken the insects 

 will never revive. 



Chloroform, when used in this manner, will be found to possess many 

 advantages over any other poison. It is quicker in its action, much 

 more convenient, and under all circumstances entirely harmless. I use 

 this form of collecting bottle both for the electric light and in the field. 

 The bottle will contain, without injury to the specimens, the captures 

 of a whole evening, or a whole day. 



If, through carelessness, so much chloroform has been poured intO' 



