NOTES ON COLLECTING, ETC. 113 



disappears almost altogether. The undersides of the Lycenas acquire 

 in the vapour of ammonia a buff tint ; but this passes off after the 

 insects have been aired. It should be borne in mind, however, that the 

 dark-coloured butterflies and C. phlceas never regain their colours and 

 beauty. It will be asked, perhaps, what I do in such cases. I first 

 stupify with chloroform, and then stab the underpart of the thorax with 

 a fine steel pen dipped in oxalic acid. Insects so treated can, and must 

 be, set at once. The idea may occur, why not kill all specimens in this 

 way ? For one or two reasons. First, perhaps, because there is the 

 suspicion that it is not the most merciful of methods. In the second 

 place specimens so killed cannot be put aside for setting ; it must be 

 done at once, or rigor mortis will prevent, and, so far as I have found, 

 the stiffening does not pass away. Then, unless very skilfully done, 

 there is danger in the stabbing process, either that the insect should be 

 spoiled by the pen, or the acid should spread over and disfigure the 

 wings. It requires a steady hand and some experience to know just 

 the amount of acid necessary for the purpose. It will be understood 

 then that I adopt this plan sitnply because forced to do so on account of 

 the action of ammonia on these particular insects. With these few 

 exceptions, there is nothing to equal ammonia in my opinion for putting 

 lepidoptera to death. — Joseph Anderson, Jun., Chichester. 



Last year I tried the experiment of killing with ammonia instead of 

 cyanide. I used it first on some Lyccena corydon, captured specimens, 

 sent me alive by a friend. It had a startling effect on their colour, 

 changing the pretty silvery-blue to a dirty bluish brown. Nor did this 

 vanish on being removed from the fumes. ^ I had most of them to 

 throw away, and those retained are only worth preserving as specimens 

 of chemical changes of colour. I tried it next on six Erebia blandina^ 

 the only results of a journey for the species made a day or two too soon. 

 They were males, fine as bred, and of a rich glossy brownish black. 

 These it changed to a dull dirty ochreous brown, which colour they still 

 retam. I tried no more, but as no mention is made by your corre- 

 spondents of any colour change in their specimens, I venture to submit 

 my painful experience. — John E. Rorson, Hartlepool. 



The Laurel Jar.— Your correspondent, the Rev. G. H. Raynor, 

 does not seem to appreciate this very useful mode of killing insects. 

 To coleopterists it is simply invaluable, and a few hints respecting its 

 preparation may perhaps be of service to others. In the first place, 

 procure a wide-mouthed glass pickle jar, with a patent lever stopper, 

 this latter is much to be preferred before cork, rendering the bottle 

 as nearly as possible air-tight, Tin boxes should be avoided, as 

 laurel kept in these soon dries up. It is highly important that the 

 laurel should be picked during dry weather. The best time is the 

 afternoon of a bright sunny day at end of May or beginning of June, 

 as the young shoots are then tender and full of sap, and are best 

 for the purpose. If picked in damp weather, the laurel sooner or 

 later turns mouldy. Lay the gathered shoots on a newspaper and 

 pound well with a hammer, so as to bruise all the stems and leaves. 



^ I cannot understand this. 1 have a drawer full o{ corydon to exhibit all the phases 

 of variation possible. The males would compare with freshly-emerged specimens m 

 colour, but all were kilKd with ammonia. — El). 



