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Mosquitos may be transferred one at a time from the biting jar, 
and from day to day killed and dissected. Chloroform and cyanide 
may be used for killing. Chloroform is more conveniently used, but 
cyanide yields better preparations when it is desired to preserve most 
of the mosquito for identification, for the reason that cyanide causes 
the mosquitos to spread their wings. 
METHOD OF EXAMINING FOR SPOROZOITES AND ZYGOTES 
First it should be said that successful dissections can only be 
obtained with killed specimens. Mosquitos that have been dead 
twelve or more hours, particularly if they had fallen on the water, 
have become so macerated that the cells of the mid-gut or salivary 
glands separate and float away, it being impossible to retain the 
organ intact. When an examination of the salivary glands is desired, 
the wings and legs of the mosquito are trimmed off with a small, sharp 
entomological knife. The distal half of the thorax, with the abdomen, 
is removed by a transverse, clean cut, the mosquito being laid on a 
piece of white cardboard. With a small pair of forceps the proboscis 
is grasped, and the specimen laid on a drop of saline solution on 
a Stender dish cover under the dissecting microscope. The chitinous 
covering of the thorax, just behind the nape, is carefully slit, or torn, 
and the muscle organ beneath loosened slightly ; then by pulling out 
the proboscis with one needle and holding the chitinous thoracic 
covering with the other, the salivary glands will be drawn out. They 
should be cut off from the head by a small, very sharp knife, and 
picked up with the point of a bright needle and placed in saline 
solution, io per cent, formalin, or films made for staining. 
The sporozoites will be seen cither free or in epithelial cells, or in 
the duct of the salivary glands; appearing as thin, slightly curved, 
spindle-shaped bodies, placed side by side, frequently as though 
matted together. 
METHOD OF EXAMINING FOR ZYGOTES 
The identified mosquito is laid on a piece of white cardboard, the 
abdomen cleanly and carefully removed by a transverse cut, just 
behind the thorax, and placed on a glass slide, or better, the under 
