Fig. 87. Cocoon of the Cecropia moth. It sometimes hangs from a twig of a fruit tree.

Fig. 88. End of cocoon of Cecropia, inside view, showing where the moth gets out.

The Cecropia moth often measures five or six inches across—a veritable giant. Its main color is dusty brown, with spots and bands of cinnamon brown and white. On each wing is a white crescent bordered with red and outlined with a black line. The body is heavy and covered with thick, reddish-brown hairs, crossed near the end with black and white lines. On its small head are two large feathery feelers or antennæ. The Cecropia moth emerges from the cocoon, full grown, in early summer, when out of doors. Those kept in the house often come out as early as March. The eggs are deposited by the adults upon apple, pear, cherry, maple and other shade and fruit trees. Professor Comstock says that the spiny caterpillars which hatch from the eggs in about two weeks, are known to feed upon the leaves of some fifty species of plants. One could therefore hardly make a mistake in offering refreshment to these creatures, since they are anything but epicures. The full-grown caterpillar, having spent the summer eating and growing, with now and then a change of clothes, is often three inches long and an inch in diameter. It is a dull bluish green in color. On its back are two rows of wart-like protuberances (tubercles), some yellow, some red, some blue. As there is nothing else in nature which is just like it, one need have no difficulty in recognizing the Cecropia in its different phases.

Fig. 89. Cocoon of Promethea moth fastened to a twig with silk.

The cocoon which this giant silk-worm weaves is shown in Fig. 87. It may be found on a twig of some tree in the dooryard, but sometimes on a fence-post or equally unexpected place. Inside the cocoon the brown pupa, alive but helpless, waits for spring.

Fig. 90. Cocoon of Promethea, cut open lengthwise to show the valve-like device at upper end through which the adult moth pushes its way out.