THE CABBAGE MAGGOT. 5 



Only one of them laid more than one egg in a place, and she 

 laid two. The eggs were carefully concealed, and were not 

 visible from the outside without disturbing the soil." 



In this connection it may be said that several eggs were 

 often found in the soil near a plant in one bunch, indicating 

 that sometimes a single fly may lay a number in one place. 



The egg, see enlarged figure on colored plate ; is white, 

 just visible to the naked eye; under the microscope showing 

 fine reticulations, and on one side an incomplete groove. 



On May i8th in the same field above referred to there was 

 hardly a plant free from eggs, showing pronounced activity 

 on the part of the fly at this time. Between this date and the 

 23rd much rain fell, and many of the eggs previously observed 

 had been washed away. At this date too, many eggs were 

 found on young plants not yet taken from the hot beds. 



Will Disturbing the Egg Prevent Hatching? Evidently 

 not, for two eggs laid Friday the i8th at 3 P. M., placed in 



Fig. 4. — Larva emerging from egg. Observed under microscope. (Author's 



illustration.) 



a vial, and considerably shaken in transportation, hatched on 

 Wednesday the 23rd, five days later. Other eggs collected 

 in the field and shaken, also hatched. 



Duration of Egg Stage. The two eggs above referred to 

 hatched in five days from time of laying. Of two eggs laid 

 on the 23rd, one hatched on the 26th, three days and about 

 five hours. It may be said then that the egg stage is from 

 three to five days' duration. 



On May 31st the first brood of flies appeared to be practi- 

 cally through with egg laying on cabbage and cauliflower, 

 for although they were observed in the field, a week's exami- 

 nation failed to disclose any laying eggs. On June ist eggs 

 were observed on young radishes, and market gardeners 

 began to report maggots in radishes. 



Laboratory Observations on Egg. On July 2nd several 

 cabbage maggot flies which had been confined under a bell 

 jar with a potted cauliflower plant, laid eggs on the ground 

 near the plant. In other zvords, the Mes bred in captivity. 



