. Animal physiology. Physiology, Comparative; Physiology, Comparative. 86 METAMORPHOSIS OF INSECTS. are the only parts deficient; these gradually make their appear- ance, and the insect is then perfect. Such is the case with the grasshopper and cricket kind; and a change of this kind is termed an incomplete metamorphosis. But in general, the change of form is much greater; for that which the egg produces has a form quite unlike that of the perfect insect, and much more resembling the lower classes of Articulata. 104. The caterpillar or maggot of many Insects is com- pletely destitute of legs;
. Animal physiology. Physiology, Comparative; Physiology, Comparative. 86 METAMORPHOSIS OF INSECTS. are the only parts deficient; these gradually make their appear- ance, and the insect is then perfect. Such is the case with the grasshopper and cricket kind; and a change of this kind is termed an incomplete metamorphosis. But in general, the change of form is much greater; for that which the egg produces has a form quite unlike that of the perfect insect, and much more resembling the lower classes of Articulata. 104. The caterpillar or maggot of many Insects is com- pletely destitute of legs; and where it does possess feet by which it may crawl, these are merely fleshy projections, and are not jointed members. The segments or divisions of the body are all equal, or nearly so, as in the worm tribe; and in its habits and mode of life, the larva (as it is termed) is en- tirely unlike the perfect insect. It is extremely vora- cious, and increases rapidly in size; and during this in- Fig. 42-silk-worm. crease, its skin is several times thrown off", and a new one formed, better adapted to its advancing growth. When it has attained its full deve- lopment as a caterpillar, it undergoes a very re- markable change, previously to which it usually forms a protection for itself; either by weaving a silken thread of its own spinning, into a case or cocoon (as is done by the silk-worm) ; or by gluing together bits of stick, straw, or dead leaves, as is done by many other insects; or by burying itself in the ground, as do most of the beetle tribe. Beneath this protection it under- goes its first metamorphosis into the state of chrysalis or pupa ; in which it remains completely or partially motionless, and. Fig. 43.—Chrysalis of the 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 Carpenter, Wil
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