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each; No. 25, Notes on Mosquitoes of the U. S., 10c.; No. 42 Some Insects attacking the Stems of Growing Wheat, Rye, Barley, and Oats, 5c.; No. 50, The Cotton Bollworm, 25c.; No. 51, The Mexican Boll Weevil,25c.

Bureau of Plant Industry—Bulletin No. 88, Weevil-resisting Adaptations of the Cotton Plant, 10c. This gives an instructive account of the struggle of a plant for existence against an insect enemy.

—Gall fly (enlarged) and oak gall with larva, and one from which a developed insect has escaped.

— A, straight wings, nerve wings, false nerve wings; B, joined wings; C, scaly wings; D, half wings; E, two wings.

ol, upper lip; ok, biting jaws; uk, holding jaws; ul, under lip; kt, jaw fingers; lt, lip fingers.