Fig. [194].—Funnel of Cyrtauchenius elongatus. (After M‘Cook.)
This description of nest seems common to all species of the genus Atypus. The American “Purse-web Spider,” A. abboti, burrows at the foot of a tree, against the trunk of which it rears the projecting portion of its silken tube. At the bottom of the nest the cavity is enlarged, and blind processes project in different directions.
Another burrowing spider, Cyrtauchenius elongatus, surmounts its silk-lined burrow by a funnel-shaped structure of pure white silk, about three inches in height and two or three inches in width. There is no attempt at concealment, and the white funnels are conspicuous among the thin grass, presenting the appearance of fungi.
The burrowing habit is also common to the Wolf-spiders or Lycosidae, but beyond a very slight lining of silk there is usually little spinning work about their nests. Occasionally there is a certain amount of superstructure in the shape of a silken funnel (Lycosa tigrina, M‘Cook), or of an agglomeration of twigs and pebbles, as in the case of the “Turret-spider” (Lycosa arenicola, Scudder).
Fig. [195].—Turret of Lycosa carolinensis. (After M‘Cook.)
A colony of our handsome species, Lycosa picta, is an interesting sight to watch. Their favourite habitat is a sandy soil, variegated with many-coloured patches of moss and lichen, among which their own markings are calculated to render them inconspicuous. The observer, by lying perfectly still, may see them silently stealing forth from their burrows in the bright sunshine, and hunting diligently in the neighbourhood, ready to dart back on the faintest alarm, or if the sun should be temporarily obscured by a passing cloud. So closely do they resemble their surroundings, that it is only when in motion that they can readily be detected. It is very curious to see them popping out their heads to ascertain that the coast is clear before venturing forth, and the utter silence of their operations adds to the eeriness of the effect. The tubes of these spiders, though without a trap-door, and only slightly lined with silk, are Y-shaped like those of Nemesia congener, the main tunnel giving off a blind branch about half-way down.
The nest of the Water-spider, Argyroneta aquatica, must not be passed over without mention. This spider, though strictly an air-breathing animal, spends almost the whole of its existence beneath the water. That it can live in such a medium is due to the fact that the long hairs which clothe its abdomen retain a bubble of air as it swims beneath the water, so that it carries with it its own atmosphere. The air-bubble which invests its body gives it a strong resemblance to a globule of quicksilver, and renders it a pretty object in an aquarium as it swims about in search of food or in prosecution of its spinning operations.
Of these the most interesting is the building of its nest. Working upon a water plant some distance below the surface, it forms a silken dome of closely-woven threads, which it next proceeds to fill with air. To do this the spider rises in the water, raises its abdomen above the surface, and jerks it down again quickly, so as to carry with it a bubble of air which it helps to retain with its hind legs. With this it swims back to its tent, into which it allows the imprisoned air-globules to escape. By degrees the dome or bell is filled, and the creature has a dry and snug retreat beneath the water. In this it passes the winter in a torpid condition. The young of this species appear to be fond of utilising the empty shells of water-snails, which they float by filling them with air, and thus save themselves the trouble of nest-construction.