He is now a very quiet and circumspect young professor. It were indeed a dangerous experiment to wiggle in such a tight suit as now incloses him, so he remains immovable and resigned. A strange process is now going on in his physiology. Hour by hour his outer skin is becoming detached from the under skin, and now he is simply inclosed within its sac. The shell of his former head has been crowded off his face, as it were, and has slid down towards the mouth of the new head within. Shortly after this feature has taken place the imprisoned caterpillar becomes restless to burst his bonds, and a quiet working motion begins, which gradually forces the skin in wrinkles towards the tail of the body, of course drawing it tighter and tighter about the head, and with it the connection from the spiracles at the sides of the body. At last, with one final effort, the skin behind the head ruptures, and discloses the new skin beneath, and through the opening thus made the new head soon appears, and the entire new suit of clothes emerges in a few moments. But though the old clothes are worked off into a little shrunken pellet at the tail, the old head-shell is still retained, being attached to the hairs immediately back of the new head, and thus retained. Five or six times in the life of the caterpillar this same process is performed, each performance leaving its token; so that our "professor" enjoys the unique distinction of being able, in his mature years, to look up to the head he wore when he was a baby or youngster, and make it useful, too, in keeping off the flies as he ponders on the flight of time.