. American spiders and their spinningwork. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits . 170, a, b) in which separate fibres cannot be distinguished. The spiral lines, according to my own studies,when examined under an ordinarj^ Jiand lens,present a milky appearance, as though composedof very thinly spun material. With a littleliigher power the supporting spiral thread is seenpassing through this milky mass. Placed undera microscope, the line is seen to consist of->threestrands, namely, the central spiral thread, andtwo
. American spiders and their spinningwork. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits . 170, a, b) in which separate fibres cannot be distinguished. The spiral lines, according to my own studies,when examined under an ordinarj^ Jiand lens,present a milky appearance, as though composedof very thinly spun material. With a littleliigher power the supporting spiral thread is seenpassing through this milky mass. Placed undera microscope, the line is seen to consist of->threestrands, namely, the central spiral thread, andtwo curled lines, which alternately cross and re-cross each other above and below the centre,forming the loops as represented at Fig. 177. Inthis respect Mr. Emerton has correctly represent-ed the spiral line of Hyptiotes. The two curledlines seemed to me to be sometimes composed ofa flocculent instead of a smooth thread, and it isthis which, seen by the eye, or by a lens of lowpower, gives the milky appearance above results I obtained from freshly spunwebs, whose clean silk was unmarred by studies of this cross line, made from older. Fif:. 175. Calamistrum of Hj-ptiotes.(After Wilder.) a, tarsus and met^atarsus of fourth leg; b, the claws,open ; c, cross section of the meta-tarsus, showing its cavity in whichlie the muscles; also a singlecurved bristle upon the side, apart of the calamistrum: e, a sim-ilar calamistrum bristle still moreenlarged; d, f, two feathered bris-tles from near the joints. ^?^- Floccu-lentThread. 176. Thread of Hypti-otes, showing oppositesides. (After Emerton.) spread out so fine snares, showed that it consists of one, two, or threeseparate threads, around or between whichthe fine flocculent material was twisted orfastened somewhat as in Fig. 178. The lat-ter presented a milky appearance, and wasthat often no traces of independent filaments were observed. In short, itwas a very delicate, cottony mass, much wider at some parts
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