The Epeiridae are the builders of the familiar wheel or orb-web. Spiders of this Family usually remain together on friendly terms for a week or more after leaving the nest. Most of the time they are congregated in a ball-like mass, perhaps for the sake of warmth, but upon being touched or shaken they immediately disperse along the multitudinous fine lines which they have spun in all directions, to reassemble as soon as the panic has subsided. Such a ball of the yellow and black offspring of the large Garden-spider, Epeira diademata, is no uncommon sight in the early autumn, and the shower of “golden rain” that results from their disturbance is not likely to be forgotten if it has ever been observed by the reader. This harmonious family life only continues as long as the young spiders are unable to feed—a period which, in some of the larger species, is said to extend to ten days or a fortnight.
Individual life then commences, and each member of the dispersed group sets up housekeeping on its own account, constructing at the first attempt a snare in all respects similar, except in size, to those of its parent.
Of course the young Spiders have not migrated far, and a bush may frequently be seen covered by the often contiguous nets of the members of a single brood. This, as Dr. M‘Cook thinks, is the true explanation of some of the cases of “gregarious spiders” which Darwin[[270]] and other naturalists have occasionally described, though social spiders exist (see Uloborus, p. 411).
Very similar habits obtain among the Theridiidae, or line-weaving spiders, a familiar example of which is the pretty little Theridion sisyphium, whose highly-irregular snare may be found on any holly bush during the summer months.
Fig. [188].—A, Pardosa sp. ♀, with young on the abdomen; B, young Pardosa detached; C, outline of the Spider with young removed. (From the living specimen.)
The Lycosidae, or Wolf-spiders, which chase their prey instead of lying quietly in ambush to ensnare it, are exceedingly interesting in their treatment of their young. The cocoon, or bag of eggs, is carried about on all their expeditions, attached beneath the abdomen, or held by the jaws, and the young spiders, on escaping from it, mount on the mother’s back, and indulge vicariously in the pleasures of the chase from this point of vantage. The empty egg-bag is soon discarded, but the brood continues to ride on the mother’s back for about a week, dismounting only to follow her as she enters her little silk-lined retreat in the ground.
During this time they appear to require no food, but they at length begin to disperse, the mother gently but firmly removing such individuals as are disposed to trespass upon her maternal solicitude longer than she considers desirable.
Many young spiders of various Families proceed immediately to seek new hunting-grounds by the aid of the wind, and become for the time being diminutive aeronauts. This habit was observed by the earliest British araneologist, Martin Lister,[[271]] as long ago as 1670, and has been alluded to by many writers since his time.
The topmost bar of an iron railing in spring or early autumn will generally be found peopled with minute spiders, and if the day be fair and the wind light, the patient observer may be rewarded by a curious and interesting sight.