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INSECTS AFFECTING TRUCK CROPS 



to cause serious results. This is self-evident. Cauliflower, when 

 not headed out, may be sprayed with Paris green. These worms 

 may also be reached by the use of poison bran mash, such as is 

 prepared for cut-worms. White hellebore may be used as a poison, 

 if timid gardeners fear Paris green. As additional measures 

 children may be hired at a nominal sum to pick the caterpillars 

 from the plants or to catch the white butterflies over a cabbage 

 field. This pest is extensively parasitized. 



FlQ. 241. Female cabbage maggot fly, much enlarged. (After Slingerland.) 



Figure 239 also illustrates the zebra caterpillar and its moth, 

 and the cabbage plutella and parasite. 



The Cabbage Maggot. The adult insect is a small fly (Pego- 

 myia brassicce Bouche) resembling the house-fly, but it is smaller. 



Life History. Eggs are laid abundantly during the spring, 

 either upon the stalk or upon the ground close to the crown of 

 the plant or upon the roots just below the surface of the ground 

 one egg being generally laid in a place. One fly deposits a large 

 number of eggs, flying from one plant to another. The egg stage 

 lasts from three to five days, and the life of the maggot is of about 



