34 MISC. PUBLICATION 336. U. S. DEPT. OF AGRICULTURE 



period, the minimum time for a complete generation would be 14 

 or 15 days. At low temperatures or with scanty food supply the 

 developmental cycle is greatly prolonged. 



ANOPHELES CRUCIANS Wied. 



There are two varieties of this species, one that breeds in fresh 

 water and the other in brackish water {26)* The adults of these 

 varieties cannot be distinguished, but the larval differences are dis- 

 tinct. The species is often the predominating anopheline in low 

 coastal-plain areas. Although both varieties are susceptible to in- 

 fection with malaria parasites, neither is known to be of serious im- 

 portance in the transmission of malaria ; in fact, the evidence at pres- 

 ent points to the contrary. It is not uncommon to be bitten by the 

 species out of doors at night or even during the day in the woods. 

 The adults also enter houses, but at Mound, La., they were always 

 found in a much smaller proportion of the total numbers present than 

 was the case with Anopheles qiiadrimaciilatus. In the vicinity of Lake 

 Apopka in central Florida, where crucians becomes extremely abun- 

 dant, the number of specimens taken while attempting to bite has 

 repeatedly been very small in comparison with the total numbers 

 present as indicated by light-trap collections. Observations made by 

 the senior author in Xew Orleans indicate that this species may mi- 

 grate for several miles when an unusual production occurs. Mac- 

 Creary and Stearns (89) obtained specimens at two lighthouses in 

 Delaware Bay, one of the locations being 3.2 miles from the nearest 

 shore, the other 5.5 miles. 



The fresh-water variety of this species occurs throughout the 

 Southeast. 



Larvae of the salt-water variety have been obtained by the writers 

 at Buras, La., Coden, Ala., Parris Island, S. C, and various places 

 on the Florida coasts. This variety has also been reported from 

 Grand Bayou (08) and Saint Bernard Parish, La. (37). Breed- 

 ing places having only a low concentration of sait (about 1.5 percent 

 or less) appear to be preferred by the larvae. 



The principal recognition characters for the female of this anophe- 

 line are the three dark spots on the anal vein and the dark-scaled 

 front margin of the wing (pi. 5, J.). The palpi are ringed with 

 white. 



ANOPHELES PUNCTIPENNIS (Say) 

 (Syn., Culex Kyemalis (Fitch), Anopheles perplexens Ludl.) 



Anopheles punctipennh ranges from the Atlantic to the Pacific 

 coast and has a variety of breeding places. In the South it appears 

 to prefer the margins of flowing streams, probably because of the 

 lower temperature of the water. Throughout the southern range it 

 occurs much more commonly late in the fall and early in the spring 

 than in the summer (6, 15). At Mound, where it was never abun- 

 dant, it disappeared almost entirely during the warm months. In 

 that vicinity pure cultures of the larvae were sometimes taken in 

 the fall in small clay borrow pits or pools free of vegetation. As a 

 rule the species is rare in central and southern Florida. The writers 



4 Since this manuscript was suhmitted for publication, specimens of a third variety of 

 this species, differing in larval characters from the other two and taken in fresh-water 

 breeding places in Georgia, have been received from R. C. Bellamy. 



