“1:30 a. m.--Larva about 21 mm., inactive and very dark, extended on lower side of leaf, front of body high, head bent, holding with third, fourth and anal prolegs. A few silk threads lie flat on leaf near caudal end of body. After some little rippling of muscle (no violent motion) the skin of the body separates from that of the head. The former is very tight; slowly, segment by segment, it is skinned backward until finally it is left, a crumpled, prickly black ball about 4 mm. in diameter, fastened to the leaf by the aforementioned silk. Meanwhile the head covering, which is all of a piece and bears two large spines, slips forward until it appears to be held in the mandibles as a hat might be held between the teeth. After a moment it falls to the ground. The caterpillar now appears somewhat short and a trifle thickened. The head, legs and prolegs are yellow, the body orange. The spines are only half size, blunt, yellow and semi-transparent. The branches appear as black hairs lying flat along the sides of the spines.” “11:33 a. m.--The spines have now attained practically their normal size, springing out with astonishing rapidity. They are still blunt, yellow and semi-transparent, but the black branches have reached normal size and assumed their proper position. The two head spines, which were curled backward, have taken on the usual angle. The head, body and prolegs now appear orange rather than yellow, the head being lightest. The drab dorsal stripe has appeared, but is very narrow. The row of depressions, one in the dorsal center of each segment, is much more conspicuous than usual.” “11:50 a. m.--Appears quite normal again, except that the spines are not quite as black, showing grayish toward the tips. The black frontal markings appear. Caterpillar rests motionless.” “12:10 p. m.--Turns about and begins to devour the cast-off skin. With the lens I watched it begin at the tip of one of the big spines and consume it clear to the root, apparently in about three mouthfuls. The head covering is never eaten.” “12:30 p. m.--Skin practically consumed. Larva rests motionless, a few of the surplus spines resting beneath the head and thorax.” PUPATION “10:00 a. m.--Caterpillar, 37 mm. long, leaves food plant and begins to wander restlessly about. “1:00 p. m.--Extended motionless, clinging to under side of window frame. “2:30 p. m.--Same position. “3:30 p. m.--Begins to lay a sparse, ragged network of very fine threads flat to the surface, covering a space of perhaps an inch square. These threads become thinner toward the periphery of the net, where they are hardly visible without a lens. “4:00 p. m.--Spins a little white silk button in the center of the network. The head moves slowly out horizontally in all directions from the button about one-half inch, swinging always back to the center. The body is fully extended, the abdomen being away from the button.