. The culture of the mulberry silkworm. Silkworms. Fig. 3.—The chrysalis: a, silkworm completing its cocoon; b, cocoon and chrysalis—cast-off skin of larva beneath; c, back view of chrysalis: d, side view of chrysalis. | Redrawn from Maillot.) state lasts from eighteen to twenty days, according to the temperature. Then the metamorphosis is complete, and the sheath breaks in the region of the head and out of the old case the moth or perfect insect issues. THE MOTH. The larva in spinning the cocoon leaves one end less dense, so that the threads open freely to permit the egress of the moth. By th
. The culture of the mulberry silkworm. Silkworms. Fig. 3.—The chrysalis: a, silkworm completing its cocoon; b, cocoon and chrysalis—cast-off skin of larva beneath; c, back view of chrysalis: d, side view of chrysalis. | Redrawn from Maillot.) state lasts from eighteen to twenty days, according to the temperature. Then the metamorphosis is complete, and the sheath breaks in the region of the head and out of the old case the moth or perfect insect issues. THE MOTH. The larva in spinning the cocoon leaves one end less dense, so that the threads open freely to permit the egress of the moth. By the aid of an alkaline fluid the moth sof- tens and parts the threads and lib- erates itself. The moth (fig. 4) comes out of the cocoon, as the larva out of the ecrg^ in the early morning hours. It has a distinct head, thorax, and abdomen, four wings, two comb-shaped antenna?, three pairs of legs, and a pair of compound eyes. Shortly after emerging, the moth deposits a liquid substance, generally white, sometimes color- less and sometimes reddish, and then the union occurs, lasting sev- eral hours, after which the eggs are laid either immediately or in the course of four or five hours. A gelatinous substance supplied by two glands near the extremity of the oviduct rovers the eggs as they come out, and causes them to adhere to the substance on which the}T are the male; b, the female. 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 Kelly, Henrietta Aiken, 1844-. Washington, D. C. : U. S. Dept. of Agriculture, Division of Entomology
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectsilkworms, bookyear19
