The caterpillars ate and grew, ate and grew. Leaves were replenished in the aquarium every couple of days.
They were eating machines, but considering they won't feed while pupating in their cocoons all winter, and won't eat as adult moths for that short cycle, it's astounding they can get by on so little for so long.
They became extraordinarily active in the fifth and final instar. This one was swaying and squirming at the end of a walnut twig and refused to pose for a decent picture.
They grew to about 4" (10 cm) long.
I was fascinated by their blue "toes." (If I were a toenail-painting kind of gal, I would paint mine the same shade in their honor.)
With such strong grippers, I can't imagine a caterpillar ever falling out of a tree.
Too soon, they began the spinning of their cocoons. They started by pulling leaves around themselves with the help of silken threads.
Silk is formed in silk glands and produced from a tube in the spinneret, located beneath the mouth.
It becomes a solid strand as it makes contact with air and is said to be, pound for pound, stronger than steel.
The cocoons were snow white at first but within a few days, turned brown and blended in nicely with twigs, branches, and dying leaves -- perfect camouflage for a long season to continue metamorphosis.
I'm at work more than I'm home and wished I'd have seen moltings and more cocoon spinnings. There are several websites that detail the life cycle more than I could:
Rearing the kids was a great experience. I'll never look at another caterpillar, moth, or butterfly in the same way.