before, and again springs her net; and this I have seen repeated in quick succession six times before the spider has ventured to make a personal approach. She has already been carried a little way toward her prey by the snapping of the net, for she always retains her hold of the apex-line by her first two pairs of feet, and the third pair serves to steady her as the slack-line slips between them. Advancing now to the junction, she seems to ascertain the exact location of the fly by pulling upon the radii.[1] Having decided, she runs along the chosen radius, and sometimes, when the prey is small, or hopelessly entangled, contents herself with pulling it up by means of the lines about it, and carries it to her accustomed station to be eaten at her leisure.
But more often she adopts a method of securing her prey which, so far as I know, is peculiar to this genus, and involves the destruction of her entire net.
Before reaching the apex (A), she cuts with her jaws the apex-line, but, as she keeps constant hold in front of the cut by her first and second pairs of feet, and has a communication in the rear through the line which most spiders always attach to a point behind them, she does not fall, neither is the net loosened beyond a certain limit; it usually seems to recoil about an inch; this recoil tends to entangle the prey like the original snaps of the net. The spider again advances, gathers the radii together and cuts them all, still keeping the line out behind; again the net recoils and collapses. Again she advances and cuts the radii; the net is now hardly distinguishable as such, and is falling together about the devoted fly; the spider now spreads her legs, gathers the net between them and flings it like a blanket over her victim; struggles are now in vain; but, "to make assurance doubly sure," the spider grasps the mass, transfers it to her third pair, and with them turns it over and over as a ball, hanging the while by her front legs, and, with the hinder pair used now alternately, drawing out from the expanded spinners broad sheets of silk which, relatively to the power of the fly, are like steel bands upon a man. Having in this way reduced the prey to a rounded ball, in which its limbs are hardly distinguishable, the spider takes it in her jaws and mounts to her place.
A single fly of ordinary size seems to occupy a whole day in the eating. When finished, the remains are cast down as a pellet, so perfectly deprived of moisture, that it is probable that this species, like the Nephila, and perhaps all Epeiridæ, sucks out the gum of its old net and reëlaborates it in her organs for use in making a new one.
Whether this peculiar economy is practised or not, it is certain that the Hyptiotes often sacrifices its whole net in the capture of a single fly; and that the making of this net involves an amount of labor and of skill which one would think not lightly to be thrown away.
- ↑ As with the Nephila, and perhaps all other geometrical spiders, this species seems to perceive light only, and not to see objects distinctly.
