MOUNTING OF MICROSCOPIC OBJECTS. 



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 protrude 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 protrude to the full extent, with all 



Fig. 4. Dissecting Scissors. 



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 potassae. The trachea and eyes, requiring different treat- 

 ment 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? 



