68i Queries and Answers, 



hoi is a most effectual method. As soon as the operation is properly per- 

 formed, the depredating insect perceives that the prepared specimen is ho 

 longer food for it, and will for ever cease to attack it. But, then, every 

 part must have received the poison ; otherwise those parts where the poison 

 has not reached will still be exposed to the enemy ; and he will pass unhurt 

 over the poisoned parts, till he arrive at that part of your specimen which 

 is still wholesome food for him. Now, the difficulty lies in applying the 

 solution to very minute specimens, without injuring their appearance ; and 

 all that can be said is, to recommend unwearied exertion, which is sure to 

 be attended with great skill ; and great skill will insure surprising success. 

 I myself have attended to the preservation of insects with the assiduity 

 which Horace recommends to poets : — " Nocturna versate manu, versate 

 diurna." The result has been astonishing success, and a perfect convic- 

 tion that there is no absolute and lasting safety for prepared specimens, 

 in zoology, from the depredations of insects, except by poisoning every part 

 of them with a solution of corrosive sublimate in alcohol. I put a good 

 large teaspoonful of well pounded corrosive sublimate into a wine bottle 

 full of alcohol. I let it stand overnight, and the next morning draw it 

 off into a clean bottle. When I apply it to black substances, and perceive 

 that it leaves little white particles on them, I then make it weaker by add- 

 ing alcohol. A black feather, dipped into the solution, and then dried, will 

 be a very good test of the state of the solution. If it be too strong, it will 

 leave a whiteness upon the feather. 



A preparation of arsenic is frequently used ; but it is very dangerous, 

 and sometimes attended with lamentable consequences. I knew a natu- 

 ralist, by name Howe, in Cayenne, in French Guiana, who had lost sixteen 

 of his teeth. He kept them in a box, and showed them to me. On open- 

 ing the lid — " These fine teeth," said he, " once belonged to my jaws : 

 they all dropped out by my making use of the savo7i arsenetique for pre- 

 serving the skins of animals." I take this opportunity of remarking that it 

 is my firm conviction, that the arsenetical soap can never be used with any 

 success, if you wish to restore the true form and figure to a skin. 



I fear that your cort-espondent may make use of tight boxes and aro- 

 matic atmospheres, and still, in the end, not be completely successful in 

 preserving his specimens from the depredation of insects. The tight box 

 and aromatic atmosphere will certainly do a great deal for him ; but they 

 are liable to fail, for this obvious reason, viz. that they do not render, for 

 ever, absolutely banefuland abhorrent to the depredator, that which in itself 

 is nutritious and grateful to him. In an evil hour, through neglect in keep- 

 ing up a poisoned atmosphere, the specimens collected by your correspond- 

 ent's industry, and prepared by his art, and which ought to live, as it were, 

 for the admiration of future ages, may fall a prey to an intruding and 

 almost invisible enemy : so that, unless he apply the solution of corrosive 

 sublimate in alcohol, he is never perfectly safe from a surprise. I have 

 tried a decoction of aloes, wormwood, and walnut leaves, thinking they 

 would be of service, on account of their bitterness : the trial completely 

 failed. Wherefore, in conclusion, I venture to recommend to your corre- 

 spondent not to put much trust in simples. 



" Contra vim mortis, non est medicamen in hortis." 

 " Against the deadly moth, can I, 

 From herbs, no remedy supply." 



— Charles Waterton. Walton Hall, June 9. 1832. 



The Tail of the Caterpillar becomes the Head of the Butterfly (p. 206. 398.). 



— Sir, The caterpillar of the genus Psyche, figured by Mr. Curtis, in his 

 British Entomology (pi. 332.), is enclosed in a case, and is frequently to be 

 seen on trunks of trees, and on rocks, where it changes to a pupa. The 



