Chambers's encyclopaedia; a dictionary of universal knowledge . in front of the spinnerets andperforated by the ducts of niiiuerous glands. Itsliresence is correlated with that of the calaiiiistrum,a single or double row of long wavy hairs on thedorsal asjicct of the second last tarsal joint of thefourth pair of walking-legs. One of the calamistrais rapidly vibrated over the cribellum, and dniwsout the secretion from the glands in the form , used to strengthen the web, to assist informing the cocoon for the eggs, and sometimesperhaps in making a domicile The webs of s]iiders vary as
Chambers's encyclopaedia; a dictionary of universal knowledge . in front of the spinnerets andperforated by the ducts of niiiuerous glands. Itsliresence is correlated with that of the calaiiiistrum,a single or double row of long wavy hairs on thedorsal asjicct of the second last tarsal joint of thefourth pair of walking-legs. One of the calamistrais rapidly vibrated over the cribellum, and dniwsout the secretion from the glands in the form , used to strengthen the web, to assist informing the cocoon for the eggs, and sometimesperhaps in making a domicile The webs of s]iiders vary as much as do thenests of birds, but as a single exani]de of theirmaking we may take that of the Common GardenU r b - w e a V e r(Epcira did-(Ivmn). The spinner first laysdown a numberof lirm founda-tion-lines, whichmay be disjiosed by hand if thesituation admitsof this, but aremore frequentlyblown fortuit-ously by air-cur-rents. Havingsecured a num-ber of thesefoundation-linesenclosing thearea for theweb, the s])iderforms the radiiwhich intersectin the Fig. 3.—Garden Sjiider spinning herweb. (From Rivcreidc*A(i(wraI Jlistonj.) This done, she begins from thecentre and Ktc])|)ing outwards in a wide spiral laysdown the spiral scallolding. Finally, beginning atthe circumference and working inwards, the spiderlays down the delicate viscid siiiials on which theelliciency of the web depends. The )irimarv spiralssimply form a scallolding, and are undone, in facteaten U]i, as they art! replaced, lint the web of theg:irdcn spider is a simple case ; wehave to distinguish orb-webs, ribboned orbs,composite snares and sectional orbs, horizontalsnares .and domed orbs, orbs and , and so on, as Dr McCook, in his incomjiar-able work on American sjiiders, has pointed out. SPIDERS 633 No structures made liy animals—not even tlienests of birds, the homes of liecs, the hills of theTermites—are more marvellous than the wehs andsnares of spidei-s. The
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Keywords: ., bookcentury1900, bookdecade1900, bookpublisherlondo, bookyear1901
