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MISC. PUBLICATION 336, U. S. DEPT. OP AGRICULTURE 



surface. Other kinds of mosquitoes hold the body more or less 

 parallel to the resting surface (fig. 9, C) , while the head and proboscis 

 are bent downward at an angle to the body. The larvae of Anopheles 

 are easily recognized by the absence of a breathing tube and by their 

 usual feeding position (fig. 10, A) parallel to the water surface. 

 Other mosquito larvae have an elongated breathing tube and while 

 at the surface hang downward with only the tip of the tube penetrat- 

 ing the surface film (fig. 10, B). Anophelines have tufts of modi- 

 fied hairs, called palmate hairs, on the upper side of the abdominal 

 segments, by which they suspend themselves just below and parallel 



Figuee 10. — Feeding positions of mosquito larvae: A, Anopheles; B, Culex. 



to the surface. While they are in this position the head is rotated 

 for feeding until the mouth parts are uppermost, and the food is 

 taken from or near the surface film. In the pupal stage the breath- 

 ing tubes are short and widely flared as compared with those of 

 other mosquitoes (fig. 11). The wings of all the typically Nearctic 

 species of Anopheles, including A. maculipennis Meig., which is not 

 known to the Southeastern States, are shown in plate 5. 



To this genus belong the mosquitoes that transmit malaria to 

 human beings, and all the species listed for the Southeastern States 

 have been proved susceptible to infection with the parasites of this 

 disease. However, Anopheles quad-rimaculatus is considered to be by 

 far the most important species concerned in the transmission of the 

 disease in this region. The others either are too rare or their blood- 



