THE CATERPILLAR AND THE MOTH
structure. On account of its large size, as compared with the size of the cocoon, the caterpillar is forced to double on itself to fit its self-imposed cell. Most of its hairs, however, are brushed off and become interlaced with the threads to forma part of the cocoon fabric. When the spinning is finished, the caterpillar ejects a yellowish, pasty liquid from its intestine, which it smears all over the inner surface of the case; but the substance spreads through the meshes of the silk, where it quickly dries and gives the starchy stiffness to the walls of the finished cocoon. It readily crumbles into a yellow powder, which becomes dusted over the caterpillar within and floats off in a small yellow cloud whenever a cocoon is pulled loose from its attachments.
The cocoon is the last resting place of the caterpillar. If the insect lives, it will come out of its prison as a moth, leaving the garments of the worm behind. It may, however, be attacked by parasites that will shortly bring about its destruction. But even if it goes through the period of change successfully it must remain in the cocoon about three weeks. In the meantime it will be of interest to learn something of the structure of a caterpillar, the better to understand some of the details of the process of its transformation.
The Structure and Physiology of the Caterpillar
A caterpillar is a young moth that has carried the idea of the independence of youth to an extreme degree, but which, instead of rising superior to its parents, has degenerated into the form of a worm. An excellent theme this would furnish to those who at present are bewailing what they believe to be a shocking tendency toward an excess of independence on the part of the young of the human species; but the moral aspect of the lesson somewhat loses its force when we learn that this freedom of the caterpillar from parental restraint gives advantages to both young and adults and therefore results in good to
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