DISEASE-BEARING AMERICAN MOSQUITOES 25 



of bristles, the anal tuft and some smaller tufts. The anal opening is 

 situated at the outer end of this segment and the tracheal gills extend 

 outward from this opening. On each side of the eighth segment, there is 

 a little patch of scales that are much used in classification." 



The pupa has a small head attached to a very large thorax, with 

 the abdomen curled around under the latter. The breathing 

 tubes or trumpets outcrop from the top of the thorax, while 

 underneath are the leg and wing cases. At the extreme end of the 

 curled abdomen are the swimming paddles by which this strange- 

 looking creature moves about from place to place. 



THE ANOPHELINAE 



Of the sub-family Anophelinae, no fewer than 6 genera, com- 

 prising at least 25 different species, are believed to transmit 

 malaria. Knab gives a list of 34 species of American Anopheles, 

 of which the following have been definitely shown to serve as 

 hosts for the malaria parasite: 



A. albimanus A. argyritarsis A. crucians 



A. intermedium A. quadrimaculatus A. pseudomaculipes 



A. tarsimaculata A. pseudopunctipennis A. occidentalis 



In addition to these, A. punctipennis has been shown to trans- 

 mit malaria under laboratory conditions, but whether or not it is 

 an important vector of malaria in nature is not yet entirely 

 established. 



The Anopheles of sanitary importance in the United States 

 are: A. quadrimaculatus, A. crucians and A. punctipennis in the 

 East and South, and A. occidentalis along the Pacific coast. 



Known transmitters of malaria elsewhere include: A. sinensis 

 in India; A. costalis in Africa; A. claviger in Spain; and A. 

 maculipennis, which is believed to be the same as .4. quadri- 

 maculatus, in other parts of Europe. 



IDENTIFICATION OF THE ANOPHELINAE 



Adult Anopheline mosquitoes may readily be distinguished 

 from all other genera by the fact that the wings are distinctly 

 spotted. Furthermore, in the female, the palpi (the slender rods 

 found on either side of the beak or proboscis) are about three- 

 quarters as long as the beak itself, while the same organs in the 

 females of other species (except one, which has a curved pro- 

 boscis) are seldom one-quarter the length of the beak. 



