REPORT ON MOSQUITOES. 353 



what irregular tessellated reticulation that disappears later, when 

 the shell becomes more transparent. 



In the previous notes it was brought out that this larva does 

 not need to come to the surface for air as much as recorded for 

 Culex. Dr. Howard iilformed me that a lot of larvae that I sent 

 him later, lived for nearly two weeks under a film of oil which 

 covered the surface of their breeding jar. 



One of my students demonstrated in the laboratory a very 

 complete tracheal system in the anal processes of the larva, so 

 we have really a gill structure, by means of which the insect gets 

 its supply of oxygen directly from the water. 



Briefly stated, the life history is as follows : The insect win- 

 ters in the larval stage, freezing and thawing as often as need be 

 during that season. It pupates late in May and becomes adult 

 a week or ten days later. Eggs are laid in the leaves singly or 

 in small groups fastened to the sides or floating on the surface. 

 The summer broods mature in about a month, and there are 

 probably three if not four series, but the broods overlap so much 

 that the breeding is practically continuous. Late in the season 

 the adults select the new leaves for oviposition even if they are 

 yet dry. 



Mr. D. W. Coquillett tells me that he has the species from 

 Florida, where it breeds in the leaves of an orchidaceous plant 

 growing on trees. 



SAYOMYIA AIvBIPKS, JOHANN. 



The White-legged Corethra. 



A medium sized yellowish mosquito, with the beak short, not 

 fitted for biting. The dorsal surface of the thorax with three 

 longitudinal, bufif colored stripes, the median not reaching the 

 posterior margin, the lateral two not reaching the anterior 

 margin. The legs and abdomen yellowish, the latter sometimes 

 with pale brown shadings. 



Description of the Adult. 



This mosquito is illustrated on plate figure no and measures 

 from 4.5-5.2 mm.,= .18-22 of an inch in length. The head 

 is pale yellow, with the exception of the black eyes. The pro- 

 boscis is about two and one-half times as long as broad, brown 

 in color, from above covered on the basal half by the labrum, 



23 MOS 



