PKESEBVATION OF INSECTS. 



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 

 vigour, 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 de- 

 vised 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 superfluous. 



This subject naturally introduces the preserva- 

 tion of the creatures after their death, and the 

 young entomologist is not perhaps sensible from 

 experience of the injury some species of insects will 

 effect in the selected specimens of others of this 

 race, and may lament, when too late, the separa- 

 tion of the wings, limbs, and bodies of his collection 

 by these tiny depredators (ptinus fur, acarus de- 

 structor). Mr. Waterton's recipe for preventing 

 this evil, I have used rather extensively, and be- 

 lieve it to be a very effectual, and generally an 

 innocuous preservative ; but as this gentleman has 

 not given us the exact proportions of his mixture, 

 it may not be useless to observe, that if one part 

 of corrosive sublimate be dissolved in eight parts 



