PSYCHE. 



ORGAN OF THE CAMBRIDGE ENTOMOLOGICAL CLUB 



EDITED BY B. PICKMAN MANN. 



Vol. I.] Cambridge, Mass., September, 1875. [No. 17. 



Bleaching the Wings of Lepidoptera. 



In the common method of destroying the scales on the wings 

 of Lepidoptera, by means of caustic alkaline solutions, for the 

 purpose of studying the venation of the wings, there is danger 

 of not arresting the action at the proper moment, and conse- 

 quently danger of destroying not only the portions which it is 

 desirable to remove, but also the scale-supporting membrane, 

 and even the delicate veins themselves. The use of a modifi- 

 cation of the chlorine bleaching process, commonly employed 

 in cotton bleacheries, obviates the necessity of removing the 

 scales at all, and leaves the wing perfect. 



There are many ways in which this bleaching can be done, 

 but I have found the most convenient method of applying the 

 chlorine to be the following. The wings must first be soaked a 

 few moments in pure alcohol, in order to dissolve out the oily 

 matter in them. If this is not done, the surface of the wings 

 acts as a repellent, and will not be moistened by an aqueous 

 solution. When the wings have become thoroughly soaked by 

 the alcohol, they are ready to be removed to a solution of com- 

 mon bleaching powder. This bleaching powder is sold by 

 druggists as " chloride of lime," but it is really a mixture of 

 calcic hypochlorite, calcic chloride, and calcic hydrate. Ten 

 parts of water dissolve the first two compounds, leaving nearly 

 all the third suspended in the solution. The solution should be 

 made with cold water, filtered, and kept in a tightly corked 

 bottle till required for use. When the wings are transferred to 

 this solution the bleaching commences, and in an hour or two 

 the wings are devoid of markings, except when the colors have 

 been photographed on the membrane, although the veins retain 



