[87] COLLECTING AND PRESERVING INSECTS RILEY. 



tion of the chlorine bleaching process commonly employed in cotton 

 bleacheries, the material for which is sold by druggists as chlorate of lime. 

 The wings are first soaked in pure alcohol to dissolve out the oily matter, 

 which will act as a repellant to the aqueous chlorine solution. The chlo- 

 rate of lime is dissolved in 10 parts of water and filtered. The wings are 

 transferred to a small quantity of this solution and in an hour ortwo are 

 thoroughly bleached, the veins, however, retaining a light brown color. 

 If the bleaching does not commence readily in the chlorine solution the 

 action may be hastened by previously dipping them in dilute hydrochloric 

 acid. When sufficiently decolorized the wings should be washed in 

 dilute hydrochloric acid to remove the deposit of calcic carbonate, which 

 forms by the union of the calcic hydrate solution with the carbonic 

 dioxide of the air. The wings are then thoroughly washed in pure 

 water and may be gummed to cards or mounted on glass slides in 

 Canada balsam, first washing them in alcohol and chloroform to remove 

 the moisture. If either of the solutions known as eau de labaraque and 

 eau de javeUe are used in place of the bleaching powder, no deposit is 

 left on the wings and the washing with acid is obviated. This process 

 does not dissolve or remove the scales, but merely renders them trans- 

 parent, so that they do not interfere with the study of the venation. 



Prof. 0. H. Fern aid (American Monthly Microscopical Journal, I, p. 

 172, 1880), mounts the wings of Lepidoptera in glycerin, after having 

 first cleared them by the Dimmock process. After bleaching and washing, 

 the wings are dried by holding the slides over an alcohol flame, and a 

 drop of glycerin is then applied and a cover glass put on at once. By 

 holding the slide again over the flame until ebullition takes place 

 the glycerin will replace the air under the wings and no injury to the 

 structure of the wings will result, even if, in refractory cases, the wing- 

 is boiled for some little time. The mount in this method must be sealed 

 with some microscopic cement, as asphalt or Brunswick black. 



A method of mounting wings of small Lepidoptera for studying 

 venation, which I have found very convenient, is thus described 

 by Mr. Howard in Insect Life, Vol. I, p. 151 : 



" Some years ago we used the following method for studying the vena- 

 tion of the wings of small Lepidoptera. We have told it since to many 

 friends, but believe it has not been published. It is in some respects 

 preferable to the so-called ' Diinraock process,' and particularly as a 

 time-saver. It is also in this respect preferable to denudation with a 

 brush. The wing is removed and mounted upon a slide in Canada 

 balsam, which should be preferably rather thick. The slide is then held 

 over the flame of an alcohol lamp until the balsam spreads well over 

 the wing. Just as it is about to enter the veins, however, the slide is 

 placed upon ice, or, if in the winter time, outside the window for a few 

 moments. This thickens the balsam immediately and prevents it from 

 entering the veins, which remain permanently filled with air and appear 

 black with transmitted light. With a little practice one soon becomes 



