said.”  This is an utter impossibility.  The skin of no living creature will contain eighty-six thousand times its own weight in a day.  I have raised enough caterpillars to know that if one ate three times its own weight in a day it would have performed a skin-stretching feat.  Long after writing this, but before the manuscript left my hands, I found that the origin of this statement lies in a table compiled by Trouvelot, in which he estimates that a Polyphemus caterpillar ten days old weighs one half grain, or ten times its original weight; at twenty days three grains, or sixty times its first weight; and so on until at fifty-six days it weighs two hundred and seven grains, or four thousand one hundred and forty times its first weight.  To this he adds one half ounce of water and concludes:  “So the food taken by a single silkworm in fifty-six days equals in weight eighty-six thousand times the primitive weight of the worm.”  This is a far cry from eating eighty-six thousand times its own weight in a day and upholds in part my contention in the first chapter, that people attempting to write upon these subjects “are not always rightly informed.”

When the feeding period is finished in freedom, the caterpillar, if hairless, must be ready to evolve from its interior, the principal part of the winter quarters characteristic of its species while changing to the moth form, and in the case of non-feeders, sustenance for the lifetime of the moth also.  Similar to the moth, the caterpillar is made up of three parts, head, thorax, and abdomen, with the organs and appendages of each.  Immediately after moulting the head appears very large, and seems much too heavy for the size of the body.  At the end of a feeding period and just previous to another moult the body has grown until the head is almost lost from sight, and it now seems small and insignificant; so that the appearance of a caterpillar depends on whether you examine it before or after moulting.

The head is made up of rings or segments, the same as the body, but they are so closely set that it seems to be a flat, round, or pointed formation with discernible rings on the face before casting time.  The eyes are of so simple form that they are supposed only to distinguish light from darkness.  The complicated mouth is at the lower part of the head.  It carries a heavy pair of cutters with which the caterpillar bites off large pieces of leaf, a first pair of grinders with which it macerates the food, and a second pair that join in forming the under lip.  There is also the tube that connects with the silk glands and ends in the spinneret.  Through this tube a fluid is forced that by movements of the head the caterpillar attaches where it will and draws into fine threads that at once harden in silk.  This organism is sufficiently developed for use in a newly emerged caterpillar, for it can spin threads by which to drop from leaf to leaf or to guide it back to a starting point.