238 HOUSEHOLD INSECTS 



be found within. When the insect is living in substances 

 like fine flour it does not build a case. 



The life history of this pest is not well known. It 

 would seem that there may be several generations 

 during a season, probably six or seven in warmer 

 latitudes. During the summer months the life cycle 

 occupies about twenty-four days, while in spring and 

 fall during cooler temperatures a much longer time is 

 required. The species apparently winters over in the 

 adult condition. 



The saw-toothed grain-beetle is fond of meal, flour, 

 and grain of all kinds. It is nearly always present in 

 granaries and has been reported in starch, tobacco, and 

 dried meats, although Chittenden says, "it is doubtful if 

 the insect will breed in such substances." It is often 

 present in dried fruits. Our records show that the beetles 

 get into macaroni, cornstarch, ginger, and mustard, and 

 that they attack dried peaches. They are often brought 

 into the house in the materials purchased at the store. 

 Moreover, the beetles have the habit of gnawing holes 

 through paper bags, thus finding their way into stores of 

 cereals supposedly well protected from invasion by insects. 

 Taschenberg, in discussing this beetle under the name of 

 Silvanus frumentarius, mentions an instance where the 

 adults invaded dwelling rooms adjacent to a brewery in 

 which grains were stored. The invading beetles developed 

 the curious habit of creeping into the beds and nipping the 

 sleepers. 



Evidently this grain beetle is widely distributed over 

 this country and over the world. Taschenberg says that 

 through commerce this species has spread over the whole 

 earth. 



