1875-1876.] I 9 I 



impaled. If on opening the killing box it is found that an insect 

 is not required it may be left on the grass, and in a short time 

 will again return to life. 



There are three different poisons I have tried; each has its 

 advantages and disadvantages. Chloroform is the most immediate 

 in its effects, and this is a decided advantage ; but it is so volatile 

 that there is much waste in using it, and the insects are apt to 

 come to life after being apparently dead. The insects that are 

 really killed by its agency are likewise rigid and difficult to set 

 properly without being relaxed. Bruised laurel leaves have the 

 advantage of preserving the insect in a flaccid condition, even for 

 days, and may, in fact, be employed to relax rigid insects ; but 

 this agent is not so rapid in its soporific effects, and there are 

 certain kinds of moths the colour of which is ruined by it. Cyanide 

 of potassium is the agent I most generally use, and on the whole 

 find it best. I do not mix it with lime or whiting, but use it in 

 the dry pure state — wrapping up one of the pieces in blotting 

 paper (as it is liquescent). I place it under the cork bottom of 

 my killing boxes, and another piece in the corner of my collecting 

 box, and in most cases I find it to answer every purpose. There 

 are some few insects, however, which seem to have the power 

 of almost entirely resisting its effects, one of which is the Burnet 

 Hawk (Z. Filipendulce), and where insects are in a very active 

 state it is scarcely rapid enough in its effects to save them from 

 much loss of beauty; I therefore carry, besides the cyanide, a small 

 bottle of chloroform — a drop or two of it is quite sufficient to 

 quiet the most restless insect almost immediately, and the cyanide 

 then completes the work. Many have complained to me of the 

 return of the insects to life again, after having been for a long 

 time exposed to the influence of the cyanide. I think it will be 

 found in these cases that the cyanide was mixed, and not used in 

 its pure state. If the insect is taken out soon no doubt it will 

 revive ; but I have not found this to be the case where it has been 

 left a reasonable time under the influence. 



And now a word about the capture itself of the day-flying 



