40 



They have long been known to infest meal, flour, grain, and veg- 

 etable stores in Europe, and in the past few years have become 

 very troublesome in this country, occasioning considerable alarm 

 among millers, flour and feed dealers, grocers, and dealers in 

 patent foods. It is not an uncommon pest in our museum collec- 

 tions, feeding on the dead bodies of insects. The adult insects 

 are small, flat, reddish-brown beetles, about three sixteenths of an 

 inch in length. Oar most common species, T. confusiim, is represented 

 in its different stages in Fig. 5 (p. 39). The eggs are deposited in 

 the flour, from which the young hatch a little later. There are four 

 or five broods daring the year. They are offensive creatures, and 

 impart a disagreeable odor to the infested material. Their carniv- 

 orous habits, however, make some amends for the mischief they do. I 

 have frequently seen the adults of both weevils preying upon the 

 larvpe and pupae of the floar moth in mills in California. In one 

 reel, where a great number of the flour- moth larvae had pupated, 

 it was rather difficult to find a single cocoon which did not con- 

 tain an adalt of either confusitm or ferrugineum, the former spe- 

 cies being, however, most abundant. The flour-moth chrysalids, 

 in most cases, had been completely devoured. 



August 18, 1895, I placed a hundred adalt beetles of confusum, 

 received August 16 in flour from Toledo, Oiio, in a breeding-cage 

 in which several hundred larva? of the flour moth had just pupated, 

 and lefr them undisturbed for several days. Augast 26, I made 

 a careful examination and found that the weevils had penetrated 

 two thirds of the cocoons and destroyed the chrysalids within 

 them. August 30, two flour moths emerged from this cage, but 

 no others issued at any time later. There was an abundance of 

 wheat flour and corn meal in the cage, which fact alone would 

 seem to suggest that the weevil prefers insect food when it is 

 available. These weevils were left in the cage undisturbed, where 

 they have been breeding continuously ever since, and there are 

 now in the cage thousands of adults and larvae. 



One enthusiistic miller in San Francisco, California, who ob- 

 served the fl )ur weevil feeding upon the larva of the flour moth, 

 made artificial breeding beds for the former and distributed them 

 about his mill in the hope of reducing the flour moth, which was 

 everywhere present in his mill. August 23, 1895, he wrote me 

 the following letter on this subject: "I had hopes of some as- 

 sistance from the little weevil, having observed them feasting on 

 the larvae of the flour moth. I cultivated colonies of them and 

 distributed them through the mill, and watched them very closely 

 for some weeks. I found that while they did attack the larvae to 

 some extent, it was still not enough to be of any particular benefit. 

 The little beetles are themselves a pest, as they get into the 

 meals and flour and make trouble there, so I have abandoned any 

 hope in that direction." 



I have seen the notorious cadelle (Tenebrioides maurUanica), 

 known, sometimes as the "bDlting-cloth beetle" in California, at- 

 tacking both the larva and pupa of the flour moth and devouring 

 both the larva and adult of the flour weevil, T. confusum, in my 



