234 



THE CANADIAN ENTOMOLOGIST. 



IV with 6 to 10, often more or less in a row, V and VI base with 

 the usual distal sensoria and not infrequently segment V bears one 

 or two near the base (Fig. 22a). Wings with black and rather 

 conspicuous veins, and the terminal branch of the media nearer the 



Fig. 22. — Aphis pseudobrassicx, \vin?ei viviparous fp-nile; a, antenna of same, enlarged; b< 



cornicle of same, enlarged. 



apex of wing than where it first branches. Legs with femur pale 

 brownish to blackish, tibia pale brownish with tip black and 

 tarsus black. Cornicles dusky, paler at tips, and shaped as in 

 the wingless form (Fig. 22b). Cauda concolorous with the abdomen 

 or paler. Measurements as follows (averages from six individuals) : 

 Length of body 1.4 mm.; width of body 0.66 mm.; length of wing 

 2.4 mm.; width of wing 0.9 mm.; antenna I, 0.069; II, 0.061; III, 

 0.363; IV, 0.191; V, 0.165; VI, base 126; VI, filament 0.35S; 

 total average length 1.333 mm.; length of cornicles 0.172 mm.; of 

 cauda 0.134 mm. 



Descriptions made from specimens collected on radish, turnip, 

 and rape, at Lafayette, Indiana. 



