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HABITS OF IMAGINES 



The female imagines of the Culicinae are almost entirely blood- 

 suckers though some are found also upon flowers. Some species are 

 the only known vectors of certain diseases, such as malaria, yellow 

 fever, and filariasis. On account of this latter fact a very voluminous 

 literature has appeared within the last twenty years, a brief list of 

 some of the more recent and important works being given at the end 

 of this summary of the family. 



Keys to Subfamilies 



LARVAE 



1. Apex of abdomen with a long respiratory tube 2 



— Apex of abdomen without elongate respiratory tube 3 



2. Antennae pendulous, hanging down in front of head and armed 



with 4 long and strong apical bristles (PI. XLI, Fig. 1), or when 

 at rest folded back against sides of head and armed with 2 or 3 

 strong apical claws Corethrinae, pt. 



— Antennae porrect, not pendulous nor folded back against sides of 



head when at rest, and usually with a few weak bristles and one 

 or two pointed processes (PI. XL, Fig. 3) Culicinae, pt. 



3. Anal segment cylindrical ; last segment with a fiat dorsal area in 



which are 2 spiracles ; thorax and abdomen without black air-sacs 

 Culicinae, pt. 



— Anal segment either bladder-like or the last segment with no spira- 



cles and the larva transparent, glass-like ; a pair of black air- 

 sacs in thorax and another in seventh abdominal segment (PI. 

 XLI, Fig. 2) Corethrinae, pt. 



PUPAE 



1. Apical abdominal appendages acutely pointed. . . .Corethrinae, pt. 



— Apical abdominal appendages rounded 2 



2. Thoracic respiratory organs elongate-oval, pointed at apex, black, 



contrasting sharply Avith color of thorax . Corethrinae, pt. 



— Thoracic respiratory organs more or less trumpet-shaped, never 



elongate-oval or pointed at apex, generally but little darker than 

 thorax (PI. XL, Fig. 8) Culicinae. 



imagines 



1. Proboscis short, not adapted for piercing Corethrinae. 



— Proboscis very long, adapted for piercing Culicinae. 



