. A manual for the study of insects. Insects. HEXAPODA, 55 plete metamorphosis; for in the case of other insects there is no distinct pupa stage. When reference is made to the young of an insect that undergoes an incomplete metamor-. Fig. 66.—A large cocoon within a rolled leaf. phosis it is called a nymph. This term is applied to all stages of such an insect from the time they hatch from the ^§"g until they shed their skin for the last time. When a nymph first hatches it has no signs of wings; but after it molts several times two projections appear on each side of the thorax. These proje
. A manual for the study of insects. Insects. HEXAPODA, 55 plete metamorphosis; for in the case of other insects there is no distinct pupa stage. When reference is made to the young of an insect that undergoes an incomplete metamor-. Fig. 66.—A large cocoon within a rolled leaf. phosis it is called a nymph. This term is applied to all stages of such an insect from the time they hatch from the ^§"g until they shed their skin for the last time. When a nymph first hatches it has no signs of wings; but after it molts several times two projections appear on each side of the thorax. These projections become larger and larger, and more wing-like in form with each successive molt. Usually the change in the size of these organs, between the last nymph stage and the adult stage, is much greater than that of any previous molt. With the nymphs of certain families, dragon-flies, crickets, grasshoppers, and locusts, the front pair of developing wings extend back beneath the hind pair instead of covering them ; and by this inverted position of the wings the nymphs may be distinguished from the' adults, even in those cases where the adults have only rudimentary wings. The Adult,—This is the last stage or the mature form of the insect. Almost all adult insects except Thysanura have wings, although there are numerous exceptions to the rule; for there are many cases where wings have been lost through disuse. An insect never grows after it reaches the adult stage, and therefore never molts. There is a popular belief that a small fly will grow into a large fly, but this is not true, for after any insect gets its perfect wings it can. 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 Comstock, John Henry, 1849-1931; Comstock, Anna Botsford, 1854-1930. joint author. Ithaca, N. Y. , Comstock Pub. Co.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectinsects, bookyear1895
