REPORT ON MOSQUITOES. 155 



The scales are replaced by a series of chitinous bars, ar- 

 ranged in a single row, 26 



■9. The anal siphon is very large and stout, dilated centrally; 

 antenna much longer than head, slender, with an even 

 outcurve or convexity, Janthinosoma musica 



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

 antenna nearly straight, slender, shorter than the 

 head, Culex janiaicoisis 



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

 longer than the head, ver\^ thick medially, bisinuate 



or with an outward and an incurve or convexity, C. discolor 



ID. The scales are not more than 15 in number and form a 



small patch, 11 



The scales number 20 or more and form a large patch, 14 



11. Anal siphon of moderate length; three times as long as 



wide, or longer, 12 



Anal siphon short, less than three times as long as wnde, ... 13 



12. 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, in a partly double row, tapering apically; 

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



Culex sylvesiris 

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



bottom; tracheal gills very long and slender, C. dtipreei 



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



tuft composed of many hairs ; tracheal gills very 



long, C. scrratus 



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



bristle ; tracheal gills short, C. triseriatus 



14. Anal siphon short, not much more than twice as long as 



broad, 15 



Anal siphon moderate, from 2^/2 to 3^ times as long as 



broad, 17 



Anal siphon long, not less than four times as long as broad, 23 



15. Stout, compact larvse; antennal tuft of several hairs, 16 



Long, slender larva, antennal tuft of i or 2 hairs; 25-35 



scales in patch; 17-21 siphonal spines with 2 or 3 



long teeth at base, C. atropalpus 



16. Scales 14-22, with stout apical and slender lateral spines ; 



13-18 siphonal spines with 2 or 3 small teeth, some- 

 times simple ; fresh water, C. trivittatus 



Scales 16-22, with rounded apex and slender lateral spines ; 

 12-16 siphonal spines with 1-4 small teeth on both 

 sides ; head maculate ; salt marsh, C. tceniorhynchus 



Scales 20-40, with stout apical and slender lateral spines ; 

 16-24 siphonal spines with 1-5 small teeth; head gen- 

 erally immaculate ; salt marsh C. sollicitans 



17. Scales rather broad, 18 



Scales elongate 19 



18. Scales 35-40, with 3 stout apical and smaller lateral spines ; 



16-20 siphonal spines with 1-3 small teeth; head mac- 

 ulate ; salt marsh breeder, C. cantator 



Scales 25-50, with one very stout apical and slender lateral 

 spine; 16-22 siphonal spines with i or 2 large and 

 4-6 smaller teeth on basal half; head immaculate; 

 fresh water form, C. can tans 



19. Only the terminal segment with a dorsal plate or ring 20 



Last two segments, with dorsal plates; antenna very short, . .C. signifcr 



20. Antenna not specially marked or colored, 21 



Antenna prominent, white at base, dark at tip, C. aurifer 



