The Atlantic Monthly, Volume 18, No. 106, August, 1866. Various

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      One morning, in the cell of a large female, I found a cocoon of beautiful yellow silk containing a rounded mass of eggs. Soon the same occurred with other females, and there were fifteen cocoons, which would give about seven thousand spiders. Early in October, just one month after they were laid, the eggs of the first cocoon were broken and disclosed little spiders with rounded yellow bodies and short legs, looking about as little like their parents as could be imagined. The eggs in the other cocoons followed in their order, and now each contained four or five hundred little spiders closely packed.

      For some time they seemed to eat nothing at all; but within a few days all had shed their skins, and now the abdomen was smaller, while the cephalothorax and legs were larger and darker; but they showed no desire to leave their cocoons. Still they grew perceptibly; and coincident with this was a less pleasing fact: their numbers were decreasing in the same proportion, and occasionally one was seen eating another. It was some time before I could reconcile the good temper and quiet behavior of the parents with this instinctive and habitual fratricide on the part of their children. But look at it in this way: here were several hundred active little creatures in a space just large enough to contain them; presently they were hungry, and as no two could be of exactly the same size, the smaller and weaker naturally fell a prey to their larger brethren, or rather sisters, for either very few males are hatched, or else they are particularly good eating, and a very small proportion survive the perils of infancy. It is evidently an established and well-understood thing among them: all seem to be aware of their destiny, to eat or be eaten. What else can they do? Human beings would do the same under the same circumstances; and I have never seen the least sign of personal spite or malignity in the spider. There is no pursuit, for there is no escape; and we can only conclude that, as the new-born fish's first nourishment is the contents of the yolk-sac, partly outside, though still a portion of its body, so the first food of the young spiders is, if not themselves, the next best thing,—each other. Thus it is provided that the smaller and less vigorous shall furnish food for the larger until the latter are strong enough to venture forth in search of other means of support.

      In consequence of this mutual destruction, aided materially by the depredations of birds and of other insects, and by exposure to the weather, only about one per cent of those hatched reach maturity. If properly protected, however, a far larger proportion may be saved; and as their multiplication is so rapid, no fear need be entertained of a limit to the supply.

      By keeping these little spiders in glass jars, inverted, and with a wet sponge at the bottom, they were easily watched and cared for. At first only about one twentieth of an inch long and nearly as wide, they increased in length as they grew, but for many weeks lived in common on an irregular web, feeding together on the crushed flies or bugs thrown to them. But when one fourth of an inch in length, they showed a disposition to separate, and to spin each for herself a regular web, out of which all intruders were kept. And now it was found that all these webs were inclined at nearly the same angle, and were never exactly vertical; that, like the spider in the first web she made in the Botanical Garden, the insect took a position much nearer the upper than the lower border; and also that, instead of a web of perfect circles laid upon regular radii, as used to be described and is still figured in our books, or even one of a spiral line, as is now more correctly described of ordinary geometrical spiders (Fig. 6), these never made a circle, nor even a spiral, but a series of concentric loops or arcs of circles, the lines turning back upon themselves before reaching a point over the spider, and leaving the larger portion of the web below her; and more than this, that the lines, though quite regular, were by no means perfectly so, as may be seen in Fig. 7, copied from a photograph.

      Fig. 6. Web of common Garden Spider.

      Fig. 7. Web of Nephila plumipes.

      As usual, the radii, or spokes, of the wheel-shaped structure are first made; then the spider begins a little way from the centre, and, passing from one radius to another, spins a series of loops at considerable distances from each other till she reaches the circumference. These first loops, like the radii, are of white, dry, and inelastic silk, and may be recognized by the little notches at their junction with the radii. The notches are made by the spider's drawing her body a little inward toward the centre of the web at the time of attaching them to the radii, and so they always point in the direction in which the spider is moving at that time, and in opposite directions on any two successive lines (Fig. 8). Having reached what is to be the border of her web, and thus constructed a firm framework or scaffolding, she begins to retrace her steps, moving more slowly and spinning now in the intervals of the dry loops two or three similar loops, but much nearer together and made of the elastic and viscid silk, till she has again reached her starting-point near the middle of the web, where, on its under side, she takes a position, head downward, hanging by her claws, and thus keeping her body from direct contact with the web.

      Fig. 8. Section of Web.

      Here she will remain quiet for hours СКАЧАТЬ