1S79.] 191 



pupifera of " Tetraneura ulmi" carrying back to the elms t]ie'^ Sexuata erostrata." 

 This is a very interesting and long looked for discovery. — J. Lichtenstein, Mont- 

 pellier : Mh December, 1878. 



On the preservation of Aphides. — I had great pleasure in reading the note on 

 Herr Schlechtendal's system of preservation of Aphides (p. 16-1 ante), and I think it 

 may also be of interest to make known the method I use. Many years ago, seeing 

 how well some fossil insects had been kept enclosed in amber or resin, I thought it 

 might be possible to imitate this mode of preservation of soft-bodied insects, and I 

 tried to do so by placing an insect on a drop of balsam on a piece of thin covering- 

 glass of appropriate size, covering it closely with another piece of glass, and fixing 

 the whole in a frame made with two pieces of card, but the experiment was not 

 satisfactory. 



Two years since I tried talc instead of glass : it is easy to cut with scissors, is 

 nearly as transparent as glass, thinner, and not brittle. Then, by dissolving a bit of 

 resin in spirit of turpentine, I make an artificial amber, a little brown in colour but 

 sufficiently transparent for my purpose, and proceed as follows : — I put a drop on a 

 square piece of talc, place my plant-louse thereon, and move it gently until it is 

 completely immersed, by which time the legs and wings are generally extended in a 

 proper position, then I put another square piece of talc on the top, and press on it a 

 little until the liquid is well expanded and the insect is entirely surrounded. Then 

 I take a frame of card and a similar piece of gummed paper, lay the prepared object 

 on the former, and cover it with the latter, previously moistened, in order to hold all 

 together, and, finally, I write the name, number, and page of my diary on the card, 

 and pin the preparation in my cabinet. The whole proceeding takes only five minutes. 

 The specimens answer perfectly for my biological studies ; they have kept well for 

 two years, and I believe will last at least as long as I shaU. More care ought of 

 course to be taken with specimens intended for embryological researches, but for a 

 collection this method is quite sufficient. The number, say '^-^, refers to the 23rd 

 page of my diary, line 5, where I read — "Pemphigus cornicularius, Pass., winged 

 " emigrant pseudogyne coming out of galls on Pistacia terebinthus, 8th Sept., 1878 

 (sent to J. W. Douglas)." — Id. 



[The specimen M. Lichtenstein had the goodness to send is very effective as re- 

 gards transparency, security, and doubtless also its durability. The compression that 

 results from the nearness of the pieces of talc to each other, would, however, often 

 be detrimental to the structure of the body of an insect, but this might be obviated 

 if the insect were surrounded by a ring of thick card on which, instead of on the body 

 of the insect, the covei-ing piece of talc should rest. — J. W. D.]. 



The tvorJcs of the late Professor Stal.— In the Ann. de la Soc. Ent. de France, 

 p. 177 (1878), is an article by Dr. V. Signoret, entitled, "Notice sur la vie etles travaui 

 entomologiques de Carl Stal," and I am indebted to the courtesy of Dr. Signoret for 

 a copy of the paper, which, by giving an enumeration of all the late Professor Stal's 

 entomological writings, will prove most valuable to Hemipterologists and other 

 workers. The work of Stal, as thus catalogued, consists of 87 memoirs, the result of 

 the labours of twenty-five years. His first paper, " Nya Svenska Hemiptera," ap- 

 peared in 1853 ; his last publication " Systema Acridiodeorum," bears the date 



