Note 179 — Chapter IX · THE SPIDER.

Her singular economy was first, we believe, described by Clerck (Aranei Suecici, Stockholm, 1757.), L. M. de Lignac (Mém. des Araign. Aquat., 12mo. Paris, 1799.), and De Geer.

“The shining appearance,” says Clerck, “proceeds either from an inflated globule surrounding the abdomen, or from the space between the body and the water. The spider, when wishing to inhale the air, rises to the surface, with its body still submersed, and only the part containing the spinneret rising just to the surface, when it briskly opens and moves its four teats. A thick coat of hair keeps the water from approaching or wetting the abdomen. It comes up for air about four times an hour or oftener, though I have good reason to suppose it can continue without it for several days together.

“I found in the middle of May one male and ten females, which I put into a glass filled with water, where they lived together very quietly for eight days. I put some duck-weed (Lemna) into the glass to afford them shelter, and the females began to stretch diagonal threads in a confused manner from it to the sides of the glass about half way down. Each of the females afterwards fixed a close bag to the edge of the glass, from which the water was expelled by the air from the spinneret, and thus a cell was formed capable of containing the whole animal. Here they remained quietly, with their abdomens in their cells, and their bodies still plunged in the water; and in a short time brimstone-colored bags of eggs appeared in each cell, filling it about a fourth part. On the 7th of July several young ones swam out from one of the bags. All this time the old ones had nothing to eat, and yet they never attacked one another, as other spiders would have been apt to do (Clerck, Aranei Suecici, cap. viii.).”

“These spiders,” says De Geer, “spin in the water a cell of strong, closely woven, white silk in the form of half the shell of a pigeon’s egg, or like a diving bell. This is sometimes left partly above water, but at others is entirely submersed, and is always attached to the objects near it by a great number of irregular threads. It is closed all round, but has a large opening below, which, however, I found closed on the 15th of December, and the spider living quietly within, with her head downwards. I made a rent in this cell, and expelled the air, upon which the spider came out; yet though she appeared to have been laid up for three months in her winter quarters, she greedily seized upon an insect and sucked it. I also found that the male as well as the female constructs a similar subaqueous cell, and during summer no less than in winter (De Geer, Mém. des Insectes, vii. 312.).” “We have recently kept one of these spiders,” says Mr. Rennie, “for several months in a glass of water, where it built a cell half under water, in which it laid its eggs.”