27 



itself, to a limited extent, when the manufactured products 

 are not available. Wliile a resident of California, being sus- 

 picious of all breakfast foods purchased for my table, I 

 closely inspected every package, and found flour-moth larvse 

 in oatmeal, corn meal, rolled wheat, and germea bought at 

 a local grocery store. They also feed on crackers, and have 

 been found in bumblebees' nests and in beehives, feeding 

 probably upon the wax and bee- bread. Mills in which several 

 kin is of cereals are prepared for food are not troubled equally in 

 all departm<^nts. For instance, where wheat flour, oatmeal, and 

 buckwheat flour are manufactured, tlie oatmeal is more infestfd 

 than the wheat flour, and the buckwheat worse than the oatmeal. 

 The manager of a California mill wrote me with reference to this 

 subject as follows: "I have observed that they seem to thrive best 

 in buckwheat flour. I have never been able to understand why 

 they should prefer this flour, but we have to be exceedingly care- 

 ful of this food, or in a short time it will become full of webs 

 spun by the larvae." The manager of a Canadian mill wrote Mr. 

 Fletcher the following: "If this insect strikes a mill where a 

 variety of cereal products are manufactured, it will work its way 

 into every product, though it likes glutinous substances best. It 

 attacked every thing we made, from pot-barley to fine farina and 

 milk food in tins " In a mill, where rice foods are the principal 

 product manufactured, the manager tells me the rice is more at- 

 tacked than any other cereal. He said they were much troubled 

 with the larvae in food put up in tin cans lined with tissue paper, 

 very often having the goods returned, marked "wormy." 



DEVELOPMENT. 



By a long series of experiments, conducted in California and 

 Illinois, I have ascertained that the life cycle of Ephestia kuehni- 

 ella under the most favorable conditio!) s, from the time the egg 

 is depo.-iited until the adult moth emerges, is about nine weeks. 



Mr. Danysz has found that the period of development in France 

 is about the same, insects in his experiments having completed 

 the life cycle in from two to two and a half months. Professor 

 Landois is of the opinion that during warm weather, in Germany, 

 the larva of the flour moth develops into the adult within four 

 weeks. In speaking of the outbreak in warehouses in London, 

 Mr. Klein says: "The larvae, which were full-fed in about three 

 weeks, then made their way to the surface." It is hardly safe to 

 assume that this represents the full life cycle of the larvae, as the 

 exact date of hatching was not recorded. 



In connection with the Canadian outbreak, Mr. Fletcher says: 

 "There are probably two normal broods of the flour moth, one 

 emerging in the spring, and another in the autumn; but in a jar 

 kept constantly under observation in my office, which was heated 

 during the winter, there have been, I judge, three distinct broods; 

 although from the fact that some retarded individuals have been 

 emerging the whole time, and no special study made of them, it 

 is very difficult to keep track of the separate broods." 



