. American spiders and their spinningwork. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits . ate coating of the spiral gum has gathered. Smallspherical objects, grains of pollen and the like, also are seen, and the orbsoon becomes well sprinkled over with minute extraneous particles, espe-cially if the wind blows or the location is dusty. Under the microscopethe beaded line shows through the substance of the globules, which isevidently aggregated around it. Indeed, one may scrape off the beads andleave the line intact. Fig. 84
. American spiders and their spinningwork. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits . ate coating of the spiral gum has gathered. Smallspherical objects, grains of pollen and the like, also are seen, and the orbsoon becomes well sprinkled over with minute extraneous particles, espe-cially if the wind blows or the location is dusty. Under the microscopethe beaded line shows through the substance of the globules, which isevidently aggregated around it. Indeed, one may scrape off the beads andleave the line intact. Fig. 84 shows a few of these viscid beads as theyappear under a microscope. The sections I, II, III are from a snare ofCyclosa caudata examined afield. Section IV is drawn from a snare ofArgiope argyrasj^is spun while in confinement. It shows the beadingalong a space of nearly five millimetres as marked off at a; and also indi-cated upon the magnified line. None of the beads upon this snare werelonger than about one-tenth of a millimetre. In shape tliey were ovoid,more or less pointed at the poles; many were globular and some had Insect Architecture, page 88 AMICKICAN SlIDEKS AND THEIR SPINNINGWDltK. iiTC<;ular forms. To the naked eye or under a eonnnon hand glass thebeads often show as quite regularly arranged globules of two or threesizes. (Fig. 85.) These two opinions aie very deeply seated in the popular mind: tirst, tiiat spiders are able to shoot out from their spinnerets lines or rays; second, that they are able to retract within the abdomen the lines Elasticity „•],;,.]( t]i(.y spin. In the former case the delicate filaments are oi bpn-al ^,j^.^^.^^^,^| from the spinning tubes as liquid silk, but the movement of the air is the means by which they are borne swiftly aloft or outward from tlie spinnerets. There is no ground in fact for the latter opinion, although it is not strange that casual observers should be deceived, as the optical illusion, for such it is, is
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