84 THE CANADIAN ENTOMOLOGIST. 



(aa) Less convex; aiuenn?e 7- or 8-jointed. 



(i) Scale with two prominent tubercles ; antennae 



8-jointed Cockerelli. 



(ii) Scale without such tubercles. 



(b) Antenna? 7-jointed : scale alt. 2^-3 mm . . .mori. 



(bb) Antennae 8-jointed. 



(c) Joints 3, 4, 5 nearly equal gefiistce. 



(cc) Joint 3 longer than 4, and this longer than 5. 



(d) 5, 6, 7 nearly equal ; scale nar- 

 rower, 3 mill, wide ; second an- 

 tennal joint with one hair only, 

 this very long elongatiim. 



(dd) 6 longer than 7, and may be longer 

 than 5 ; scale broader, 4^4 mm. 

 wide ; second antennal joint wiih 

 two long hairs .. . .viagnoHarum. 



(3.) Long. 7 mm. 



(a) Convex, alt. usually 5 or 6 mm. 



(i) Antennae 8-jointed ; legs short and robust, tarsus longer 



than tibia Douglasi. 



(ii) Antenntie 7-jointed \ tarsus shorter than tibia. 



(b) Legs long and slender coryli. 



(bb) Legs robust ; scale higher, alt. 5 mm ulini. 



(iii) Antennae 6-jointed ; legs robust, tarsus shorter than tibia ; 



scale highest of this group ; alt. 6 mm caprece. 



{ulmi ^ud. caprece are probably one species.) 

 (aa) Less convex, alt. not over 4 mm., usually less. 

 (i) Antennae 8-jointed. 



(b) Not pruinose; legs ordinary rosarum. 



(bb) Pruinose ; anterior legs with tarsi very 



broad : berberidis. 



(ii) Antennae 7 jointed, joints 3 and 4 about equal ; legs 

 ordinary 



(b) Pruinose with a whitish powder priiinosiim. 



(bb) Not pruinose. 



(c) More convex, 4 mm. high quercifex. 



(cc) Less convex, not over 3 mm. high. . .mori. 



