136 THE MICROSCOPE. 



— then proceed to clip the wings off close to the body, which, not 

 needing any preparation, may at once be placed in alcohol, in 

 one of the covered porcelain saucers. The legs, being cut off, 

 should be placed in liquor potassae, which should be contained in 

 the glass pomatum jar with a cover. By gently pressing the abdo- 

 men, the ovipositor will protude to its full length, and should then 

 be cut off close to the body, and also placed in the liquor potassae. 

 The tongue should be pressed out in like manner, and when found 

 (under the magnifying glass) to protude to the full extent, with all 

 its parts, should in like manner be cut off and follow the legs and 

 ovipositor. Then the abdomen may be cut open with the scissors^ 

 the viscera washed out with the small sable brushes and water, and 

 the skin or epidermis containing the spiracles be placed in the liquor 

 potassce. The trachea and eyes, requiring different treatment to 

 that we are now pursuing, will not be followed further at present. 



The length of time necessary for the various parts to remain in 

 the liquor potassae, varies materially. Thus an hour, or at the most, 

 two, will suffice for the tongue and ovipositor, whereas the legs and 

 epidermis will require an immersion of not less than one or two 

 days. Great care should be taken to remove them before too much 

 color is abstracted, as the beauty of a preparation is quite lost if it 

 be pale and colorless. A good rule is to remove these parts from 

 the liquor as soon as they assume a lightish brown appearance; 

 placing them in water, and carefully washing and brushing them 

 with the sable brushes. One of the nest saucers will be found a 

 most convenient vessel for doing this in. They should then be 

 transferred to a glass slip, taking care (with the tongue) so to 

 spread it out with the needles as to show the lobes and false trachea, 

 and (with the feet), to show the hairy pads. When properly spread 

 out, place another glass slip over them so that they are pressed flat 

 between the two, and wrap tightly with a piece of fine brass wire, 

 which for this purpose should be cut in lengths of lo or 12 inches. 

 The wire is recommended, rather than thread of any kind, because 

 there are no fibres to become entangled with the specimen, 

 and thus mar its beauty; and it may be used many times over. The 

 slips thus wrapped should then be dropped into a vessel of water, 

 and left for some hours. On being taken from the water and the 

 wire removed, the slips should again be placed in a saucer or small 

 plate of water, and carefully separated to avoid marring or injuring 



