198 Mosquitoes 



have some, put up four years ago, on which the 

 liquid has not been renewed. If it irritates the 

 fingers, grease them, or wear thin rubber gloves or 

 tips. If it is necessary to clear a specimen more 

 than the acid will accomplish, place it for a few 

 hours in liquor potassae. * The best method of 

 mounting the head and genitalia is first to dehydrate 

 with absolute alcohol, put on chloroform, then 

 mount in chloroform balsam. Dissecting should 

 be done in a weak salt solution, about .05 per cent, 

 will do. To secure the alimentary canal, the simplest 

 way is to pull off the wings and legs and separate the 

 last two abdominal segments. Then, by holding the 

 base of the forelegs and pulling on the separated 

 segment, the alimentary canal can be drawn out. 

 The ovaries will be found in the posterior part of the 

 abdomen. It is very hard to work out the salivary 

 glands, but they may be obtained by picking off the 

 top of the thorax and gently pulling off the head. 

 The soft parts do not make good permanent 

 mounts. 



In collecting larvae it is best to go two or three 

 days after a rain, as the larvae from the eggs which 

 were on the ground and hatched by the down- 

 pour are now developed far enough to be plainly 

 visible when scooped up in the dipper. If one waits 

 more than four days in hot weather there will be 

 nothing much, in the case of many species, but pupae 

 and pupa skins. The enamelled-ware dipper shows 

 the larvae best. When they are scooped up, they will 

 make for the bottom of the dipper, and it may be so 



1 Smith. 



