256 Mosquitoes 



26. Tufts K and M on segment five, both with four 



or more hairs 27 



Tufts K and M not having four or more hairs 

 each 29 



27. Seventh and eighth segments having H, four- 



haired; D, five-haired; G, one-haired. Breathing 

 tubes over six times as long as wide. Segments 

 four and five, with one long tuft above margin. 



Culex pipiens. 

 Seventh and eighth segments not having H four- 

 haired. Without the other above combination 

 of characters 28 



28. Having one or two long, single hairs on the ven- 



tral half of segments six to eight. D, three- 

 haired, G, two-haired. Breathing tubes four 

 times as long as wide. Segments four and 

 five each with two tufts, one of them short, just 



above margin Culiseta consobrinns. 



Having no conspicuous single hairs on ventral 

 half of segments six to eight. Tubes decided- 

 ly flaring and truncate. Without above com- 

 bination of characters Melanoconion atratus 



29. With H sub-obsolete on segments four to seven 



or four to six; if so on four to seven, with 

 four-haired tuft on ventral margin of segment 



five 30 



With H well developed on segments fourto seven. 

 With at most a two-haired tuft on segment 

 five 32 



30. Single hair dorsad of H on segment nine. Tufts 



K and M on segments four to seven, of over 



two hairs Oclilerotatus canadensis. 



Single hair represented by a tuft on segment nine. 

 Tuft M t sometimes K also, on segments four 

 to seven, with three or more hairs 31 



