KILLING OF INSECTS. 265 



death ensues. A crow-quill must be shaped into a 

 point, like a rather long pen, this point dipped into the 

 prussic acid, and an incision made with it immediately 

 beneath the head into the middle of the shoulders of the 

 creature, so as to permit the fluid it contains to enter 

 into the body of the insect. Immediately after this, in 

 every instance in which I have tried it, a privation of 

 sensation appears to take place, the corporeal action of 

 the creature ceasing, a feeble tremulous motion of the 

 antennae being alone perceptible ; and these parts seem 

 to be the last fortress that is abandoned by sensation, as 

 they are the primary principle of sensibility when life 

 is perfects extinction of animation ensues, not a mere 

 suspension, but an annihilation of every power, muscu- 

 lar and vital. As one example of the decisive effects 

 of this fluid, I shall instance the common wasp, a crea- 

 ture so remarkably tenacious of sensation, or so long 

 retaining a muscular power, that it may remain, as every 

 one knows, for days crushed in the window, an appa- 

 rently dead insect, yet upon pressing the head, the sting 

 will be so protruded as to give a very sensible pain to 

 the finger it should meet with ; but upon the prussic 

 acid being injected into this creature as above, when in 

 full vigor, in the course of less than half a minute a 

 loss of vitality ensues, the action of the muscular fibre 

 ceases altogether, and no pressure can incite it again 

 into action. The sudden effect of this liquor is not so 

 generally known as from humanity and expediency 

 might be wished. Who first devised the experiment I 

 am ignorant ; but any repetition of means whereby a 

 necessary end can be obtained by the least painful and 

 brief infliction, will hardly be considered as super- 

 fluous. 



This subject naturally introduces the preservation of 

 the creatures after their death, and the young ento- 

 mologist is not perhaps sensible from experience of the 

 injury some species of insects will effect in the select- 

 ed specimens of others of this race, and may lament, 

 when too late, the separation of the wings, limbs, and 

 bodies of his collection by these tiny depredators (ptinus 

 fur, acararus destructor). Mr. Waterton's recipe for 

 X 



