FIELD BOOK OF INSECTS. 



The larvae of T. obscurus (Plate LXXXIV) 

 and molitor are the large Meal-worms, which 

 have the distinction of being, probably, the only insects 

 injurious to man's goods which are purposely bred on a 

 large scale for commercial purposes. They destroy large 

 quantities of flour, meal, cereals, and the like but are 

 bred and sold for soft-billed birds to eat. The larvae 

 are hard, cylindrical, and strongly resemble wire-worms 

 (Elateridae). That of obscurus is about an inch long, when 

 full-grown; yellow but shading off into yellowish-brown at 

 each end and where the segments join. That of molitor 

 is somewhat lighter. The pupae are whitish and about 

 .6 in. long; most of the abdominal segments have fringed 

 side-expansions and the last one ends in two spines. The 

 adults of both species are black or dark reddish-brown and 

 about .6 in. long; molitor is shiny and obscurus is not. 

 They are frequently attracted to lights. There seems 

 to be, normally, but one generation a year, but in heated 

 buildings this is not very definite. Related species occur 

 under bark. 



Nyctobates pennsylvanica is a black beetle, nearly an 

 inch long, which is often common under the loose bark of 

 dead trees. The genus differs from Tenebrio by the tarsal 

 pubescence being fine and silky. The antennas do not 

 reach to the back of the pronotum, which is not narrowed 

 at the base. 



We have two species of this genus which 

 Tribolium . . ,. 



occur in meal, grain, and other vegetable 



products. To give them a common name different from 

 that applied to Tenebrio, they have been called Flour 

 Beetles, but neither name is very distinctive. Tribolium 

 ferrugineum is reddish-brown; its head is not expanded 

 beyond the eyes at the sides ; its antennal club is distinctly 

 three- jointed; and its length is less than .2 in. Its "cousin," 

 confusum (Plate LXXXIV), is darker; its head is expanded 

 on each side in front of the eye; antennal joints gradually 

 broader at tip. It has been recorded as breeding in pepper 

 as well as in a variety of milder, starchy foods and it 

 also eats the eggs and larvae of other meal-feeding insects. 



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