INSECTS INJURIOUS TO CABBAGE, ETC. 



315 



denly appear sick, many are found wilting, and soon die. Exami- 

 nation of the roots shows that they have been riddled by small, 

 white maggots as shown in Fig. 263. Early-planted cabbage, 

 cauliflower and radishes are particularly affected, and later in the 

 season the maggots will be found on turnips and wild mustard. 



These maggots are the larvae of a small fly, resembling the 

 house-fly, but distinctly smaller, being only one-fourth inch 

 long, with a narrower body and proportionately larger wings. 

 It is a grayish color with three dark stripes on the thorax and one 





FIG. 264. The cabbage maggot fly (Peqomyia brassicce Bouche), female, 

 greatly enlarged. (After Slingerland.) 



along the middle of the abdomen, and the body bears numerous 

 stiff hairs or bristles. The flies appear just as early cabbage is set 

 out, in late April and early May in New Jersey, and in late May in 

 southern Minnesota. They do not fly far and seem to avoid fields 

 which are swept by the wind. 



Life History. The females deposit their eggs on the stem of 

 the plant or in the soil near the stem, at or just beneath the surface 

 of the soil, each female laying some fifty eggs. The eggs are most 



