86 



PROTECTIOX OF PLAXTS. 1917-18 



Cabbage Louse (Aphis brassicae Linn.). A, winged female; B and C, apterous females: 

 D, Antenna of: A E, antenna ot B and C. 



Bean Aphis (Aphis nimicis L.)^Occurs on the tips of horse and broad beans 

 at time of flowering. When the lice are abundant the plants assume a sooty 

 sickly appearance. Also on apple, dahlia, dock, shepherd's purse, pigweed, snow- 

 ball and burning bush. This aphis is slaty blue or black, \\ith white bands on the 

 legs and often with waxy tufts. Called also the "black fly," "collier" and "black 

 dolphin." 



Strawberry Root Louse (Aphis forbesi Weed). — Bluish-green, on roots of 

 strawberry; occurs also on leaves. Eggs laid on stems and leaves. Ants carry lice 

 to roots. Of no economic importance in Ontario. 



Aphis gossypii ; a, winged female; b, yoimg nymph or larva; c, last stage of nymph; 

 d, wingless female; all 'enlarged. (From Chittenden.) 



