. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 106 THE SCOLYTID BEETLES. This species is easily separated from its nearest relative, the Doug- las fir beetle, by its smaller size and eastern distribution, and from eastern forms by its medium size, convex and deeply grooved declivity, the character of its gallery, and its occurrence in Fig. 64.—The eastern larch beetle: Distribution map. (Author's illustration.) BIBLIOGRAPHY. Schwarz, 1888, p. 175; Packard, 1890 (under Dendroctonus ), p. 903; Harring- ton, 1891, p. 27; Hopkins, 1898&, pp. 104-1
. Bulletin. Insects; Insect pests; Entomology; Insects; Insect pests; Entomology. 106 THE SCOLYTID BEETLES. This species is easily separated from its nearest relative, the Doug- las fir beetle, by its smaller size and eastern distribution, and from eastern forms by its medium size, convex and deeply grooved declivity, the character of its gallery, and its occurrence in Fig. 64.—The eastern larch beetle: Distribution map. (Author's illustration.) BIBLIOGRAPHY. Schwarz, 1888, p. 175; Packard, 1890 (under Dendroctonus ), p. 903; Harring- ton, 1891, p. 27; Hopkins, 1898&, pp. 104-105; Hopkins, 1899a, pp. 394, 447; Hopkins, 1909, pp. 117-121. No. 13. THE DOUGLAS FIR BEETLE. {Dendroctonus pseudotsugae Hopk. Figs. 65-69.) The Douglas fir beetle is a stout, reddish to blackish-brown, cylin- drical barkbeetle, 4 to 7 mm. in length, its head broad, convex, with shallow longitudinal- groove behind the middle; the pro thorax short, broad, punctured, with sides somewhat rounded and strongly nar- rowed and constricted toward the head; the elytra with rather coarse rugosities between the rows of punctures; the declivity convex, with striae deeply grooved and intervening spaces convex and nearly smooth or roughened, and the body with numerous long hairs. (See tig. 65.) It attacks injured, dying, felled, and living Douglas fir, bigcone spruce, and western larch, wherever these trees grow from British Columbia southward into New Mexico, Arizona, and Cali- fornia. It excavates long, straight, or slightly winding egg galleries through the inner bark, and grooves the surface of the wood, the eggs being placed in alternate groups along the sides; the long larval. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States. Bureau of Entomology. Washington : G. P. O.
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