If we examine a chrysalis we are able to make out, through the thin envelope, all the external organs of the body stowed away in the most orderly and compact manner. The antennæ are very conspicuous, folded down alongside of the legs; and precisely in the centre will be seen the tongue, unrolled and forming a straight line between the legs. The unexpanded wings are visible on each side—very small, but with all their veinings distinctly seen; and the breathing holes, called spiracles, are placed in a row on each side of the body.
The duration of the chrysalis stage, like that of the egg, is extremely variable, and dependent on difference of temperature. As an instance of this, one of our common butterflies has been known to pass only seven
or eight days in the chrysalis state; this would be in the heat of summer. Then, in the spring, the change occupies a fortnight; but when the caterpillar enters the chrysalis state in the autumn, the butterfly does not make its appearance till the following spring. Furthermore, it has been proved by experiment, that if the condition of perpetual winter be kept up by keeping the chrysalis in an icehouse, its development may be retarded for two or three years beyond its proper time; while, on the other hand, if in the middle of winter the chrysalis be removed to a hothouse, the enclosed butterfly, mistaking the vivifying warmth for returning summer, makes its début in ten days or a fortnight.
CHAPTER II.
"COMING OUT"—ICHNEUMONS—THE BUTTERFLY PERFECTED—ITS WINGS—LEPIDOPTERA—MEANING OF THE WORD—MICROSCOPIC VIEW—NEW BEAUTIES—MAGNIFIED "DUST"—THE HEAD AND ITS ORGANS—THE TONGUE—THE EYES—THE ANTENNÆ—THEIR USES—INSECT CLAIRVOYANCE—AN UNKNOWN SENSE—FORMS OF ANTENNÆ—THE LEGS.
We now arrive at the last stage, the consummation of all this strange series of transformations; for veritable transformations they are to all intents and purposes; though some learned naturalists have discovered—or imagined so—that the butterfly, in all its parts, really lies hid under the caterpillar's skin, and can be distinguished under microscopical dissection; and that, therefore, the so-called transformations are merely the throwing off of the various envelopes or husks, as they become in turn superfluous, as a mountebank strips off garment after garment, till lastly the sparkling harlequin is discovered to view; or, in more exact language, they consider these changes in the light rather of successive developments and emancipations of the various organs than as their actual transformations. Still, it seems to me, the difference is chiefly one of terms. The real wondrous fact remains undiminished and
unexplained; that a creeping wormlike creature, in process of time, is changed into a glorious winged being, differing from the former in form, habits, food, and every essential particular, as widely as any two creatures can well differ, as widely as a serpent from a bird, for instance.
As the imprisoned butterfly approaches maturity, a change is observable in the exterior of the chrysalis, the skin becomes dry and brittle, usually darkens in colour, and if the enclosed butterfly be a strongly marked one, the pattern of its wings shows through, often quite distinctly.