I06 INSECTS INJURIOUS TO VEGETABLES 



The Seed-corn Maggot (Pcgomya fiisciccps Zett.).— When 

 the seeds of beans, peas, corn and other plants fail to 

 develop, damage is frequently due to a maggot which works 

 by scraping the seeds, sprouts, roots, stalks, and stems of 

 plants underground.' Where this insect works decay soon sets 

 in and the plants die. Entire plantings are sometimes destroyed, 

 but when only a few seeds or sprouting plants are attacked, 



Fig. 62.— Four-spotted bean v,-e3v:i. a. EeeJe: b. larva; c, pupa 

 All enlarged. (Author's illustration, U 3. Dept. Agr.) 



injury may escape notice. Early crops suffer most and if they 

 can be preserved until larger growth they will as a rule sustain 

 considerable attack without material damage. 



The insect in question is called the seed-corn maggot and 

 bean fly, and its parent looks like a small house fly. It can be 

 identified by the male (fig. 63,0)." The female can scarcely be 

 distinguished from related species, such as the adults of the 

 cabbage root-maggot and onion maggot. The length is about 

 one-fifth inch and the wing expanse about two-fifths. The larva 

 is footless and of cylindrical form (d) , narrowed at the anterior 

 extremity and enlarged posteriorly. It is considerably smaller 



1 Injury of this character is also committed by wireworms, white grubs and 

 some other insects, e. g., weevils in the seeds. 



- His principal characteristics consist of a row of short, rigid, bristly hairs 

 of nearly equal length on the inner side of the posterior tibiae or shanks. 



