Annual report of the North Carolina Agricultural Experiment Station . placed in a different class, because of themature form being a small moth which does no damage other than tolay eggs; and the same may be said of all the grain pests that develop CORN WEEVILS AND OTHER GRAIN INSECTS. 7 into moths. The remaining grain insects, which are different formsof beetles in the mature stage, do not belong to the group of snoutbeetles, and are not properly called weevils. The Rice Weevil (Black Weevil) (Calandra oryzw, Linn). The name corn weevil or black weevil is usually applied to thisspecies, altho
Annual report of the North Carolina Agricultural Experiment Station . placed in a different class, because of themature form being a small moth which does no damage other than tolay eggs; and the same may be said of all the grain pests that develop CORN WEEVILS AND OTHER GRAIN INSECTS. 7 into moths. The remaining grain insects, which are different formsof beetles in the mature stage, do not belong to the group of snoutbeetles, and are not properly called weevils. The Rice Weevil (Black Weevil) (Calandra oryzw, Linn). The name corn weevil or black weevil is usually applied to thisspecies, although its original name is rice weevil, so called because ofits being first discovered in that grain. The former names are alsoaj)plied to a near relative, the granary weevil; hence we should pre-serve the title rice weevil to make this species distinctive. India isthought to be its native home, but the species may now be found innearly every grain-producing country of the world, and is particularlyabundant in the Southern States, but is less numerous farther Fig. 1.—The Rice Weevil or Black Weevil; a, full-grown larvae; b, pupa from beneath; c and d,adults—about five times natural size. Injury is caused by the adult beetles eating into grain for food andshelter, as well as by the larva? that feed inside the kernels. Smallgrains like wheat and rice furnish food for only a single larva in eachkernel, but in corn three or four may mature. It has been estimatedthat one pair will, in the course of a year, produce over 6,000 de-scendants. The effect on the grain is to reduce the weight materially,and consequently its selling value, and renders the grain unfit for hu*man consumption. DESCRIPTION AXD LIFE-HISTORY. The mature weevils (Fig. 1, c and d) average to measure about one-sixth inch, including the snout, which is about one-third the length ofthe body. The general appearance is dark reddish-brown, but individ-uals vary from a light brown to nearly black; the thorax pre
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