Let us repeat our caution, that this definition is only applicable to _inactive_ pupæ. In the active pupæ the same development of new organs takes place, but it does not interfere with the usual actions of life. We must also add, that some of the pupæ which we must call inactive, nevertheless are not wholly without motion, but are capable of manifesting that life is in them, death-like though they appear, by slightly moving the lower part of the body.[J] All inactive pupæ, however, are without the power of moving about.
At the risk of being thought tedious, it has been indispensably necessary to be thus precise upon this point; a little careful study of these two or three pages will fix the distinctive characters of the pupa firmly in the reader's memory, and will enable him to find the account given of its history clear, easy, and interesting.
Having thus defined what the pupa state is, let us take up one of these withered objects, and by a little gentle treatment, with the assistance of a delicate scissors, a sharp pointed penknife of very keen edge, and two or three pins, we shall succeed in unrolling the insect mummy. In order to obtain the best sight of what the pupa case contains, it will be advisable to select as large a pupa as can be procured. Those of the butterfly tribe are well suited for this purpose. If we are pretty fortunate in our dissections, we shall succeed in discovering, that within the membrane-like skin there is exhibited a beautiful spectacle of order and neatness. The legs, and wings, and other external appendages, are folded down close to the body of the insect. The feet are often crossed smoothly over the breast, and the wings are flattened against the side of the body; the antennæ are also neatly arranged parallel with the legs; and altogether the insect presents a very singular appearance, from the fact of all its organs being thus smoothed down, compressed into the smallest compass, and enveloped by the external skin. The mummy appearance is very striking in some pupæ, as in the specimen figured. The appearance of the folded limbs is indistinctly exhibited in the companion pupa. All the parts of the perfect insect can be distinctly traced, if the pupa is sufficiently matured.