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Chapter XV 111 

 ANOPHELINAE THE LARVA AND NYMPH 



THE LARVA 



The larvae of Anophelines when first hatched out 

 are minute characteristic creatures, with very black 

 heads and transparent bodies. They move with a 

 very active wriggling movement. They can, even at 

 this stage, be distinguished from the larvae of Culicines, 

 especially with the aid of a lens, as they take up a 

 horizontal position. 



Examination of the Larva. This may be done 

 either in the fresh state, when also the process of feeding 

 can be well observed, or a mounted specimen is 

 prepared, and for detailed examination this is best. 



Method I. Boil the larva in ten per cent, potash 

 for half to one hour, until it is fairly transparent. 

 Wash out in water all traces of potash. Stain, if 

 required, in a saturated alcoholic solution of fuchsin 

 (basic). Dehydrate in alcohol, clear in oil of cloves, 

 mount in balsam (Newstead). This method gives 

 beautiful results, and should be used if the larva 

 mounted by method II is not sufficiently transparent. 



Method II. Place the larva in about ten per cent, 

 formalin. When dead, dehydrate in alcohol ; clear 

 in oil of cloves (or xylol, etc.), mount in balsam. 

 Place two strips of cardboard under the coverglass in 

 order to support it. 



Method III. Cover the larvae in a drop of 

 water, with a coverglass, and examine with one-half 



