316 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



abundant in late May and early June in central New York. Usu- 

 ally a female lays but one or two eggs on a plant and prefers to lay 

 them in a crevice of the stem or very near it, for if the young mag- 

 gots have to travel far to reach their food, many will die before find- 

 ing it, and if laid on hard soil the maggots will be unable to pene- 

 trate it to the soft tissue of the root, as they are unable to feed on 

 the hard stem above ground. The eggs are about one twenty- 

 fifth inch long, of a pure white color, which renders them easily 

 seen against the soil by one familiar with them, and are of the 

 shape shown in Fig. 265, having a curious ridge along one side. 

 The eggs hatch in from three to ten days, averaging five to seven. 

 The little maggots at once commence rasping the surface of the 

 tender roots, gradually mine into them, and in three or four weeks 

 have become full grown. The grown maggot is one-third inch 

 long, white or yellowish in color, tapering toward the head and 

 obliquely truncate at the tip of the abdomen. From 

 the head a pair of strong, black, hook-like, rasp- 

 ing jaws project downward, and just back of the 

 head on either side is a minute, light brown, fanlike 

 projection (Fig. 2676), or spiracle, which leads into 

 the breathing system. The oblique posterior end 

 is surrounded by twelve rounded tubercles and in 

 of cabbage the centre are two brownish spiracles (Fig. 267a). 



maggot, When done feeding the larva burrows one-half to 



firrGELtJ. v 6 n ~ 



larged; hair one inch under the surface of the soil, and the outer 



line at center s fo u gradually hardens until it forms a firm brown 

 natural size; shell, called a puparium, within which the larva 



b, outline of transforms to a true pupa. Frequently the puparia 



side view. 



(After Sling- are found in the galleries made by the maggot or in 



erland.) crevices of the roots. During the summer this stage 

 lasts about two weeks, but in the fall most of the insects remain in 

 this condition over winter. Thus the whole life cycle from egg to 

 adult requires about six to ten or twelve weeks, according to the 

 temperature and moisture, and the second generation of flies appear 

 in June in New Jersey or by mid-July in southern Minnesota. The 

 maggots of the second generation seem to do but little damage. 

 The life history of the insect during late summer has not been 

 satisfactorily determined, but there is undoubtedly a third genera- 

 tion and in the South, possibly a fourth, the work of the last gen- 



