76 ECONOMIC ENTOMOLOGY 



nearly black, one-third inch long. — Cadelle (Tenebroides 

 mauritanicus) , p. 326. 

 (b) Large insects, concealed in the bottoms of bins, corners, and the like, 

 feeding upon flour, meal or bran. Adults large black beetles; the lar- 

 vas, large, cylindrical, wormlike creatures, resembling wireworms. 



1. Adult not quite black in color, shining, its third antennal joint not 

 quite twice as long as the second; larva light yellowish, shining. — 

 Yellow Meal-worm Beetle {Tenebrio molitor ), p. 327. 



2. Adult black and without luster, its third antennal joint thrice as 

 long as the second; larva very dark, shining. — Dark Meal-worm 

 Beetle {Tenebrio obsctiriis), p 328. 



VI. INSECTS INJURIOUS TO ROOT CROPS 



(Turnips, rape, mangels, and carrots) 

 (Consult Bull. 52 C E. P., Ottawa, and Bull. 60, 111. Exp. Sta.) 

 Roots: 



(a) Tips of roots of young carrots with rusty patches on surface, or rust colored 



tunnels in the pulp, due to slender yellowish- white maggots. — Carrot Rust 



Fly {Psila rosce), p. 262. 



(6) Roots of turnips bored or tunnelled by minute grubs or maggots. — Turnip 



Flea Beetle (Phyllotreta vittata); Cabbage Root Maggot {Phorbia brassicce), 



P- 273- 

 (c) Roots cut off. — Wireworms, White Grubs, Cutworms, pp. 185, 293, 302. 



Stem and Leaves: 



(a) Young plants cut off at the ground. — Cutworms, p. 185. 



(b) Surface of first leaves of turnip and rape eaten into small holes by small 

 active black striped beetles. — Turnip Flea Beetle {Phyllotreta vittata), p. 314. 



(c) Leaves partly consumed by pale-green caterpillars. — Cabbage Worm {Pieris 

 rapce), p. 175. 



{d) Leaves eaten by caterpillars with black and yellow stripes. — Zebra Cater- 

 pillar {Ceramica picta), p. 188. 



(e) Leaves wilt and turn yellow, with presence of greenish lice.- — Turnip Plant- 

 louse {Aphis brassica), p. 148. 



(/) Young leaves eaten into holes and irregular blotches by small active green 

 caterpillars. — Diamond Back Moth {Plutella mactilipennis), p. 232. 



(g) Under-surface of leaves covered with a very fine loose web; leaves yellow- 

 ish in patches, and minute red objects present. — Red Spiders, p. 367. 



(A) Leaves eaten by red beetles with black stripes (Prairie Provinces). — Red 

 Turnip Beetle {Entomoscelis adonidis), p. 309. 



VII. INSECTS INJURIOUS TO THE POTATO CROP 



Tubers: 



{a) Surface of tuber eaten and eyes sometimes destroyed so that growth does 

 not take place; or holes bored in the tuber. — White Grubs, Wireworms, 

 Millipedes, p. 369. 



