. Bulletin of the Department of Agriculture. Agriculture. THE WESTERN CABBAGE FLEA-BEETLE. d except in a few darker individuals from northern Colorado, the normal color being almost uniformly cupreous or copper-colored. The species is also apt to he confused with Pli. aeneicollis Cr., but the latter may be readily distinguished, inasmuch as it is more convex, more shining, and distinctly Q The egg is light yellow, glistening, of oval form, and about 1/50 of an inch in length. In confinement eggs were deposited in cracks in the soil about the roots of the cruciferous plants-on whi
. Bulletin of the Department of Agriculture. Agriculture. THE WESTERN CABBAGE FLEA-BEETLE. d except in a few darker individuals from northern Colorado, the normal color being almost uniformly cupreous or copper-colored. The species is also apt to he confused with Pli. aeneicollis Cr., but the latter may be readily distinguished, inasmuch as it is more convex, more shining, and distinctly Q The egg is light yellow, glistening, of oval form, and about 1/50 of an inch in length. In confinement eggs were deposited in cracks in the soil about the roots of the cruciferous plants-on which the larva subsists and there is good reason to believe that this is the usual habit under field con- ditions. LARVA. The larva (fig. 2, a,h) is thread-like in appearance, uniformly white, ex,cept for the head sclerites, the legs, and a chitinized area on the caudal abdominal segment, which are pale chestnut brown. The mature larva is about 5 mm. in length and from to mm. in width, or approximately 10 times as long as wide. The larvffi feed normally on the roots of cruciferous plants and remain con- cealed in the soil throughout their life. \ -/ ^-—/ ^ On reaching maturitv the larva selects ^ , , T . 1 J. " J. J Fig. 2.—^\estern cabbage flea-beetle: a, a suitable place for transformation and OutUne of larva, lateral view; 6, head then wriggles about until it has formed and thoracic segments of same, dorsal ^Y 11 1 r: 1 11 • xi- -1 view; c, pupa. Enlarged. a compact, well-denned ceil m the soil, in the vicinity of the roots on which it fed. After the cell is formed the larva shortens and in about two days changes to pupa. The pupa (fig. 2, c) is approximately of the same size as the adult and is ent-rely white. The arrangement of the antennse, legs, and wings is the same as that of the average halticine pupa.^ DISTRIBUTION. The range of the western cabbage flea-beetle, accorded by Horn and others, is from the Dakotas to Mexico and central and southern Calif
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