70 ENTOMOLOGICAL NEWS. [Feb., '13 



Antennae arise from near middle of sides of head ; the mouth 

 brushes forming a club at sides of mouth; a very large 

 species Psorophora ciliata 



6. The scales of the eighth abdominal segment are separate 8 



The scales of the eighth abdominal segment, 5 to 8 in number, 



are arranged on a band 7 



The scales are replaced by a series of chitinous bars, arranged in 

 a single row 22 



7. The anal siphon is very large and stout, dilated centrally ; antenna 



much longer than head, slender with an even outcurve or 

 convexity Aedes sayi 



The anal siphon, shorter, stout, dilated nearer the base; antenna 

 nearly straight, slender, shorter than head.. Aedes jamaicensis 



The anal siphon is short, stubby, not dilated ; antenna much longer 

 than the head, very thick medially, bisinuate or with an out- 

 ward and an incurve or convexity Aedes discolor 



8. The scales are not more than 16 in number and form a small 



patch 9 



The scales number 20 or more and form a large patch 12 



9. Anal siphon of moderate length, three times as long as wide or 



longer 10 



Anal siphon short, less than three times as long as wide n 



10. About 12 elongate scales in a single row; 12-16 siphonal spines, 



each with one moderate-sized tooth, and sometimes a few 

 very small ones below it Aedes fuscus 



Scales 10-15, m a partly double row, tapering apically; siphonal 

 spines 14-18, simple or with 2 or 3 teeth ....Aedes sylvestris 



Scales 7-12 in patch; a small translucent species, feeding at bot- 

 tom; tracheal gills very long and slender Aedes dupreei 



Scales 6-7 arranged in a curve; tracheal gills long, slender, uni- 

 formly tapering Aedes abserratus 



11. A stout black species, the thorax white-banded; antennal tuft 



composed of many hairs; tracheal gills very long, 



Aedes serratus 

 An elongate slender gray species ; antennal tuft a single bristle ; 



tracheal gills short Aedes triseriatus 



A large, robust, light species ; anal siphon bottle-shaped, outer 



half linear; anal gills slightly longer than width of ninth 



segment Coquillettidia perturbans 



12. Anal siphon short, not much more than twice as long as broad. 13 

 Anal siphon moderate, from 2% to 3% times as long as broad. .15 

 Anal siphon long, not less than 4 times as long as broad 21 



13. Stout compact larva ; antennal tuft of several hairs 14 



