INSECTS AFFECTING CEREALS, ETC 



113 



time to propagate they soon couvert the Hour into a gxay useless mass. 

 A part of the annoj-aiice to purchaser, dealer, and manufacturer is due 

 to the fact that tlie insects are highly offensive, a few specimens being 

 sufficient to impart a disagreeable and persistent odor to the infested 

 substance. 



THE CONFUSED FLOUR BEETLE. 



{TriboHinn confusnm Duv.} 



The most injurious enemy to prepared cereal foods is undoubtedly the 

 above-mentioned species. Singularly enough, in less than iwo years 

 from the time of its first recognition as a distinct spuecies occurring in 

 this country, this insect had been reported as injurioifs in nearly every 

 State and Territory in the Union. The divisional ex])erience of a sin- 

 gle year, 1894, shows that more complaints are made of injuries by 

 this than of any other granivorous species. Mr. W. (r. Johnson, in the 

 American Miller of January 1, ISOG, speaking of this insect as a mill 

 pest, says that it was the most troublesome species of the year 1895, 

 and expresses the 

 belief that it had 

 cost the millers of 

 the United States 

 over 8100,000 in 

 manufactured i^rod- 

 ucts during that 

 year. 



The mature i n - 

 sect is shining red- 

 dish brown in color 

 a n d resembles in 

 miniature the 

 adult of the fa- 

 mi liar meal-worm 

 (Tenebrio), which 

 will be referred to 

 further on. It is 



scarcely a sixth of an inch long, being almost an exact rounterpart of 

 the rust-red flour beetle { T. ferrufjineum)^ with which it has been gen- 

 erally confused, but may be distinguished by the structure of the 

 antenna^, which are only gradually clavate, by its broader head, the 

 cheeks being expanded at the sides and angulated at the eyes. The 

 thorax above is gradually narrowed behind, its hind angles being more 

 or less acute. The adult beetle is shown, enlarged, in tlie accompanying 

 illustration (fig. 52) at a, and the head and antenna', still more enlarged, 

 at e. Tlie same parts of fernigincum are i)resented at /'for comparison. 



This species, like nearly all the others that frequent the family store 

 room, is what is termed a general feedei*. It prefers, however, prepared 

 cereals, and hence is most troublesome in flour, corn meal, oatmeal, 

 21470~Xo. 4 S 



'"^"^f 



r-^' 



Fig. Z2.—Tribolium confiisum: a, beetle: b. larva: c. pupa — all enlarged; 

 d, lateral lobe of abdomen of pupa; e, lieail of beetle, showing an- 

 tenna; /, same of T. fentigineum — all greatly enlarged (author's 

 tration). 



illii.- 



