192 



of variation, possibly seasonal, and a slight differ- 

 ence in the bands on the palpi and legs is not 

 sufficient in itself to constitute a difference in 

 species. 



Other characteristics that are useful for the 

 determination of species are the , male genitalia, 

 and the character of the ungues in the male, 

 whether having one or more teeth. The position 

 of the cross-veins has also been used, but this is 

 so variable in the same species that it has little 

 value. 



Characters of the Larvae and Ova. — In the 

 Anophelina, as in the rest of the Culicidae, this is 

 a most important means of differentiation. Mos- 

 quitoes that otherwise are almost indistinguish- 

 able are readily separated by their larvae being 

 different. 



One precaution must be taken. It must be 

 quite certain that it is the larva of the mosquito 

 in question that is being examined. The easiest 

 way to make sure of this is to carefully examine 

 the larva first, and then to hatch out the mosquito 

 and then examine it. The examination of the 

 larvae is considered later. 



Genus I. Anopheles. — Wings unspotted or 

 slightly spotted. Mostly belong to temperate 

 climes or hill districts. 



A. bifurcatus and A. maculipennis transmit 

 malaria. A. punctipennts has experimentally given 

 negative results. 



Costa Uniform, Wings spotted. 



1. A. maculipennis. — Wing with four spots ; 

 apex cif first tarsal joint spotted. Europe. 



2. A. crucians. — White spots on brown 



