1896.] . 63 



Wood naphtha as a relaxing medium fur Coleoptera. — In this Journal (vol. xxxi, 

 p. 21) Dr. Knaggs has described a method devised by Mr. Clark of relaxing insects, 

 meaning apparently Lepidoptera, by the use of wood naphtha. It may be of 

 interest to know that I have found the plan very successful for relaxing and 

 resetting Coleoptera. It is always difBcult to extend the limbs of the small Scaly- 

 tidcB at which I have been lately working. If relaxed in moist air, they must be 

 fixed on their backs by gum, in order to hold them in position while the legs are 

 extended one by one. It often happens that by the time the gum is dry enough to 

 secure them firmly, they have themselves become somewhat brittle and rigid. With 

 wood naphtha I have had no trouble whatever. The specimen is floated off the 

 card, and is washed till all gum is removed from the under-side, an easy task, unless 

 gum tragacanth has been used. It is then gummed on its back, and when fixed, is 

 well wetted with a brushful of naphtha ; the limbs are usually pliable at the end of 

 a minute, if not, the naphtha may be re-applied. When the limbs are extended the 

 spirit is allowed to evaporate, the specimen is then floated off, washed free of gum, 

 and mounted in the usual way. If it is necessary to release a single limb or antenna 

 only, the naphtha may be applied to that part alone. At present I have tried 

 naphtha on no other Coleoptera, but for ScolytidcB I find it more handy than water, 

 enabling the whole process of relaxing and re-mounting to be carried out in twenty 

 minutes or so. If that detestable material, gum tragacanth, has been used to stick 

 down unset specimens, it must be carefully worked off the under-side and limbs 

 with a moist brush. As it contains a constituent insoluble in water or any other 

 available medium, it is most difiicult to get rid of, but if not removed, it infallibly 

 leads to breakages. Those interested in the relaxation of Lepidoptera may like to 

 have their attention called to a paper by E. Eering in the Stettiner Ent. Zeitung 

 (1895, pp. 235 — 242), in which recent methods are discussed. — W. F. H. Blandford, 

 48, Wimpole Street, London, W. : January ^Oth, 1896. 



Black Pins. — Whilst the winter is still upon us, and collecting practically at a 

 standstill, it appears to me to be a good time to ask entomologists and collectors if 

 they I'ealize what the rage for unnecessarily fine black pins is likely to result in. I 

 take it that it will be generally admitted that a pin is an implement, the best that 

 has been devised up to the present, on which to mount an insect, so as to afford an 

 easy and safe mode of handling it, either for examination or removal. Do we attain 

 this end by the present system ? I think not. 



In the first place the process of japanning requires the application of considera- 

 ble heat ; the pins are, in fact, baked. This is immaterial so far as regards larger 

 pins, such as the black mourning pin of commerce, but with fine entomological pins, 

 probably cut from German wire, the process of baking so anneals the metal, that, in 

 the majority of cases, it renders the pin as pliable as pack thread. 



Japanning has a further disastrous effect, inasmuch as it blunts the pin, and, 

 instead of being a sharp instrument, capable of being forced by a gentle pressure 

 through any ordinary paper and cork, the present fine black pin generally refuses to 

 penetrate, either by force or persuasion, not unfrequently crumpling up, to the com- 

 plete disintegration of the insect upon it ; or, if the matter is not so disastrous as 

 that, we have all, I suppose, experienced disappointment on finding the pin trans- 

 formed into a fair average specimen of a crochet hook and fit for nothing. 



