It is now, as we say, in its quiescent or dormant condition, but we must not suppose that it is always in a profound sleep, nor can we say that it is insensible to its surroundings. Touch it gently or surprise it with a puff of air from your mouth, and it will begin to wag its pointed tail, sometimes with such vigour as to send the body rolling round and round in its box. Lay it on a bed of cocoa-nut
fibre or finely sifted soil and let it remain quite undisturbed for a few hours or days, and you will probably find that, by occasional movements of its body, it has made a slight depression in its bed, and lies partly submerged. I have known some chrysalides to completely bury themselves in this way during the course of a day or two, and others to partly expose themselves after having been lightly covered. Others again, I have observed, will move smartly if a strong light is suddenly turned on them. Many, too, certainly appear to have a strong objection to exposure to the direct rays of a hot sun; for, when thus exposed, they will struggle persistently, as if to work their bodies into some shady corner. I would not advise a young entomologist to try this experiment, however, if he values the pupæ he possesses, for direct sunlight is undoubtedly very harmful to many species, and perhaps it is to all.
Some chrysalides are not nearly so active as has just been represented; in fact, there are many which seem to show no signs of life during the greater part of the time spent in that state. But in all, whether apparently active or not, certain important internal changes are at work. We have already noticed that, even in the last days of the larval existence, some of the organs of the future imago are to be traced. But these are as yet imperfectly developed. We have also observed that a continuation of these changes, gradually carried on, would be impossible in a voracious feeder; so the insect, now fully grown, and no longer requiring a supply of food, settles down in perfect quiet, submitting itself quite passively to any further changes that nature may demand.
It has already suffered the loss of its claspers. Its wonderful jaws that did so much damage (for good or evil as the case may be) to the vegetable world are now gone, and the bulky digestive apparatus has rapidly dwindled to useless dimensions. These and other changes, already in progress, have to be perfected while the creature is in a restful and helpless condition, though they may often be retarded or even suspended during cold weather when progress would certainly bring it to an untimely end.
But now the grandest of all these transformation scenes is nigh at hand. The protective skin is already loosening from the almost perfect imago, and consequently feels softer and far more yielding than it did when in close contact with the body: the swaddled butterfly or moth (for such the pupa is) is slowly preparing to throw off its imprisoning garb. The wings and large
compound eyes are assuming their final colours, which now begin to show themselves through the more or less transparent skin, and the long legs, the perfectly formed antennæ, and the slender proboscis, all of which are folded closely under the creature's thorax, now begin to move within their loosened sheaths.
Now let us watch it closely, for one of the most wonderful sights ever witnessed by a naturalist is about to be presented to our view. We think we can observe slight movements; and, it may be, we can actually see the struggling insect endeavouring to set itself free. The legs and proboscis are moving within the loosened skin; and lo! as we watch these motions, the prison wall bursts with a slight snapping noise (at least, such is the case with some of the larger species), and in a moment out pop a few long legs which immediately struggle for a foothold. The proboscis also appears, alternately lengthening itself out and coiling into a spiral, as if impatient to reach the sweet nectar from the bottom of some fragrant flower cup.
Fig. 36—A Butterfly, just after Emerging.