14 ASSOCIATION OF ECONOMIC ENTOMOLOGISTS. 



instances laying within four hours of the time they were confined and 

 frequently placing their eggs in the axils of the leaves. 



The hatching of two eggs was observed. In each case the larva 

 appeared to emerge from the egg through the groove on the side. 

 One egg was observed to hatch under the microscope, the active 

 larva trying unsuccessfully for several hours to free itself from the 

 shell, and finally dying. The smooth surface of the glass may have 

 been, and probably was the cause of its failure to extricate itself 

 from the egg. Two other eggs, which were placed under observation 

 immediately after being laid, hatched in five days from the time of 

 laying. Another egg hatched in three days and five hours. Evi- 

 dently the egg stage lasts from three to five days. The two eggs 

 referred to as hatching in five days had been considerably shaken in 

 a vial in being transported from the field to the laboratory; hence 

 disturbing the egg evidently does not necessarily prevent hatching. 

 The larvae, judging from observations made this season, evidently 

 require twenty to twenty-one days, under ordinary conditions, to 

 reach maturity. 



A lot of maggots which changed to pupoe June 6 emerged as flies 

 June 19 and 20. Evidently, then, the pupal stage in Minnesota may 

 have from thirteen to fifteen days' duration. 



We are losing faith in the use of carbolic emulsion as employed 

 against this pest, and believe that cultural methods may possibly 

 prove our best means of control. Young maggots lived in the labo- 

 ratory for two hours and twenty minutes immersed in carbolic emul- 

 sion, 1 part to 30 parts of water, and adult maggots required three 

 hours and forty minutes' immersion before dying. Some eggs 

 hatched after thirty seconds' treatment in carbolic emulsion at the 

 same strength. On the other hand, good results were obtained by 

 immersing the roots in hellebore and water at time of setting, using 

 1 part of hellebore to 2 parts of hot water, allowing it to cool before 

 being used. The plants were immersed deeply enough to coat the 

 lower part of the stems and were immediately planted and made an 

 excellent showing. Good results were also obtained, in a protective 

 way, by the use of bran and glue and sawdust and glue, the sawdust 

 being mixed with glue in the proportion of J pound of the former to 1 

 quart of the latter. The glue was not at all thick, but rejDresented 2 

 pounds of hard glue in 1 gallon of water. When bran was used the 

 proportions were the same. The mixture was rather more sloppy than 

 good chicken feed. It was applied by hand about the base of the 

 plant, put well up on the stem, the diameter of the mass where it came 

 in contact with the ground being about 4 inches. One quart was 

 sufficient for 15 plants. The stuff quickly hardened and, though it 

 softened somewhat during summer rains, did not disintegrate. Plants 



