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On an Easy Method of Preparing Insects for the 



Microscope. 



By Staniforth Green. 



(Read April 27th, 1883.) 



My experience in mounting insects for the microscope extends 

 as far back as the year 1861. For the first five or six years I was 

 content to follow the then prevalent method of soaking the insect 

 in liquid potash, which dissolved its muscular structure and left 

 nothing but its empty skin. In that condition it was easy enough 

 to arrange legs, wings, &c, in proper position, but the result was 

 not satisfactory, as the shape and beauty of the insect was entirely 

 lost by the pressure employed in squeezing out the decomposed 

 tissues. This became more apparent to me on my becoming 

 possessed of a binocular microscope, and I at once took to mount- 

 ing insects without pressure. I found no difficulty in making them 

 sufficiently transparent without the aid of liquid potash, but was 

 sorely troubled in endeavouring to arrange them in proper posi- 

 tion. Legs would double up and wings would not remain expanded. 

 It is only very recently that I have overcome the difficulty, and as 

 this new method of mine may also be novel to other amateur 

 mounters, I will endeavour to describe the treatment as clearly as 

 possible. 



On capturing an insect, consign it at once to the poison bottle if 

 convenient, and there let it remain until it is quite dead. Do not 

 let it lie in the bottle for longer than half an hour. Ten minutes 

 is generally sufficient. The action of the cyanide of potash would 

 in a few hours injure materially the muscular structure of the in- 

 sect, and spoil it as a microscopical object. You should remove 

 the inseet before its legs and wings have become rigid ; but first 

 have ready a small piece of glass, on the surface of which spread a 

 thin film of rather stiff Canada balsam. Then place the fly, or 

 any other insect you may be operating on, lightly upon the Canada 

 balsam film in the position you desire. If a dorsal view is re- 

 quired, and a winged insect the subject, place it back upwards, 



