. A manual for the study of insects. Insects. LEPIDOPTERA. 271 these worms from the sharp-eyed birds. If so, we should have been still more interested in them; and we should have been even more so could some one have told us of the transformation of these loopers first into pupae and then into beautiful moths. But in those days comparatively few people thought it worth while to study insects. The larvae of Geometrids have as a rule only the last two pairs of prolegs well developed ; and hence, as the middle part of the body is not supported, they are unable to walk in the way that other caterpillars walk. It is probable, however, that the loss of the first three pairs of prolegs is the result of the looping gait rather than the cause of it. That is to say, the ancient Geometrid lar- vae acquired the habit of looping, after which the prolegs under the middle of the body, being unnecessary and not used, dwindled away in succeeding generations. In the case of a few members of this family three or even four pairs of pro- legs have been re- tained. The Geometrid lar- vae are mostly leaf-eat- ing, and some species, as the Canker-worms, occur in such large numbers as to be serious pests. The pupae are slender, and some species are green or mottled in color in this state. The pupa state is passed in a very flimsy cocoon or in a cell in the ground.. Fig. 322.—Wings of Caripeia angusttoraia.. 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 work.. Comstock, John Henry, 1849-1931; Comstock, Anna Botsford, 1854-1930. joint author. Ithaca, N. Y. , Comstock Pub. Co.