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Orb Web Builders
Among the large spiders which weave extensive, net-like snares for the capture of their prey, the best known is the common garden spider (Aranea products), which spins its great cart-wheel web suspended between trees and bushes across clear spaces in the bush or athwart the garden path, where it seldom fails to enmesh the head and face of the late home-comer. The female spider is robust and broad of body. Her color varies from yellowish-brown to black, and the darker forms often bear a clearly-defined white pat-tern on the back. The male is an in-significant little fellow who hovers uncertainly in the outskirts of the web of his prospective mate, and, although he spins a small web on his own account, is seldom noticed by the casual observer.
By day the female orb-weaver hides among the matted foliage near the site of the web, but at dusk she becomes active and sets about the construction of her snare which is composed of both plain and adhesive threads laid down at the will of the architect. One aspect only of the complex work of web-spinning can be considered here: the laying down of the foundation cable from which the net is suspended. How does the spider place her line across the often considerable space between the supporting trees or bushes?
The spider engineer ascends to some prominent branch or other object and pays out a silken thread. This is caught and carried away by the wind until the free end becomes entangled in the foliage of some adjacent tree. This forms the suspension cable for further work, and is greatly strengthened by the spider crossing and recrossing the line and laying down additional threads as she goes. No control is possible by the spider to guide the line in any desired direction; it is directed solely by the prevailing wind. Sometimes several at-tempts must be made before the line becomes securely fixed to enable further construction to proceed. The snare constructed, the spider hangs head-down wards in its centre, or sometimes in some adjoining place of concealment, her foot resting upon a taut thread. extending from web to retreat. This acts as a telegraph line, whose vibrations warn her of any successful capture.Although the web of the garden spider does not appear to be particularly strong, a number of records exist of birds and small bats becoming ensnared in its meshes. These birds are usually of weak flight, such as fairy-wrens, and the like. Such captures are accidental, and cannot be considered as normal items in the spider's diet. But when the spider is fortunate enough to ensnare such game, it does not hesitate to make a meal of it, pulping the flesh between the fang-bases and extracting the juices.
The eggs are enclosed in a sac of fluffy silk, often partially enclosed in leaves and suspended close to the web. Soon after hatching, the swarm of tiny spiderlings disperses in an unusual way.
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