Silk-worms proceed from eggs which are deposited during the summer by a grayish kind of moth, of the genus palæna. These eggs are about equal in size to a grain of mustard seed: their color when first laid is yellow; but in three or four days after, they acquire a bluish cast. In temperate climates, and by using proper precautions, these eggs may be preserved during the winter and spring, without risk of premature hatching. The period of their animation may be accelerated or retarded by artificial means, so as to agree with the time when the natural food of the insect shall appear in ample abundance for its support.
All the curious changes and labors which accompany and characterize the life of the silk-worm are performed within the space of a very few weeks. This period varies, indeed, according to the climate or temperature in which its life is passed; all its vital functions being quickened, and their duration proportionally abridged, by warmth. With this sole variance, its progressions are alike in all climates, and the same mutations accompany its course.
The three successive states of being put on by this insect are, that of the worm or caterpillar, of the chrysalis or aurelia, and moth. In addition to these more decided transformations, the progress of the silk-worm in its caterpillar state is marked by five distinct stages of being.
When first hatched, it appears as a small black worm about
- [Footnote: produced more worthy of our admiration than such an animal coming upon the
stage of the world, and playing its part there under so many different masks?" The ancients were so struck with the transformations of the butterfly, and its revival from a seeming temporary death, as to have considered it an emblem of the soul, the Greek word psyche signifying both the soul and a butterfly; and it is for this reason that we find the butterfly introduced into their allegorical sculptures as an emblem of immortality. Trifling, therefore, and perhaps contemptible, as to the unthinking may seem the study of a butterfly, yet when we consider the art and mechanism displayed in so minute a structure,—the fluids circulating in vessels so small as almost to escape the sight—the beauty of the wings and covering—and the manner in which each part is adapted for its peculiar functions,—we cannot but be struck with wonder and admiration, and allow, with Paley, that "the production of beauty was as much in the Creator's mind in painting a butterfly as in giving symmetry to the human form."]
