250 HOUSEHOLD INSECTS 



orris root, snuff, slippery elm flour, peanuts, peas, beans, 

 and seeds of various kinds that are stored a long time. 

 They are also pests in the museum, for they attack the 

 bodies of insect specimens. 



Chittenden cites an instance in which a whole consign- 

 ment of baking powder was lost through an infestation 

 by this insect. It seems that wheat flour had been used 

 to adulterate the powder and probably it was this that 

 attracted the insects. The boxes had all been wrapped 

 tightly with paper so that they were practically air-tight. 

 The beetles must have gained access to the powder in 

 the factory before the boxes were closed. 



The life history of this pest has not been completely 

 worked out and it is not clearly understood. The small 

 white eggs are laid in crevices of the receptacle or are 

 attached to the sides of the bags or boxes or other con- 

 venient surface. It would appear, from our own observa- 

 tions, that they are laid among the cereal on which the 

 beetle is working, especially on the hard lumps of which 

 we have spoken. These hatch into the tiny white larvae, 

 which later become light brown in color. The larvae 

 probably attain their growth in about four weeks and then 

 change to pupae. Chittenden found that the insect passed 

 through its whole life cycle in about thirty-six days. He 

 estimated about six days as the period of incubation and 

 about six days for the pupal period. There is evidently 

 an opportunity for several generations during a season, 

 and, as we have shown, they will breed in warm, evenly 

 heated rooms all winter. 



Methods of control. — Many times, when the beetles 

 become abundant in a flour bin or in wooden compart- 

 ments in which various cereals may be stored, they are 



