28 INJURIOUS INSECTS OF 1904. 



However, while millers in Minnesota can secure at some time, 

 during almost any winter, a temperature sufficiently low to kill 

 by freezing, yet such a condition is not always present, even in 

 Minnesota, when wanted (if outbreak occurs in early spring and 

 summer for instance), and surely millers in the South could rarely, 

 if ever, take advantage of this method. The bisulphide method 

 (not fumigation) must of necessity have to be resorted to, when 

 temperature conditions are not favorable for freezing. 



In one or two mills subjected to this freezing process fire had 

 to be kept in the basement, and a sufficiently low temperature 

 could not be secured, the treatment in consequence resulting un- 

 satisfactorily. See also results of experiments by the Entomolo- 

 gist on pages 29 and 30. In one mill, however, where the entire mill 

 was exposed to severe cold for eight days or more, the process was 

 an absolute success. It must be noted, however, that if millers in 

 close proximity do not co-operate in work against this moth, the 

 pest will reappear even if it is to all appearance eradicated from a 

 mill. Further, as noted below, eggs are not always killed by low 

 temperature. 



Observations and Results of Experiments by the 

 Entomologist. 



Mating and egg laying; time elapsing 'between laying of egg and hatching of 

 same. 



Pairing is evidently protracted, one isolated pair under observation remain- 

 ing in copiilo four days. Ovipositing in one case lasted six days, a female begin- 

 ning egg laying on February 9th and continuing until the 15th, on which date 

 she died. During this time the one female laid 247 eggs. These eggs began 

 hatching on the i8th, nine days after the first were laid, a recording thermom- 

 eter registering an average temperature of 70 degrees Fahr. in the room during 

 that time. Two freshly laid eggs were measured, each measuring .6 millimeters 

 in length by .35 millimeters in breadth, or, in round numbers, 1/42 of an inch 

 long by 1/63 of an inch in breadth. Three other laying females deposited 

 respectively 242, 157 and 239 eggs. 



The flight of the Moth: The question as to whether moths would fly from 

 one mill to another suggested observations along this line. The insects if left 

 to themselves did not fly in the morning. Late in the afternoon and in the 

 evening after the light was turned on, an assistant reports them flying freely 

 across the room, although not attracted to the lights, but rather avoiding them. 

 Observations elsewhere indicate that they will fly at least no feet, and proba- 

 bly farther. 



