. American spiders and their spinning work. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits. Spiders. 54 AMERICAN SPIDERS- AND THEIR 1. In Full Orb snares the spiral concen- trics cross all the radii, appearing to form complete circles. (See Fig. 47.) They are divided into Simple and Compound snares. a. A Simple orbweb is simply an orb of radiating straight lines crossed by spiral or looped lines. The snare of the Furrow spi- der (Epeira strix) is a typical example. b. A Compound orbweb adds to the sim- l)le orb
. American spiders and their spinning work. A natural history of the orbweaving spiders of the United States, with special regard to their industry and habits. Spiders. 54 AMERICAN SPIDERS- AND THEIR 1. In Full Orb snares the spiral concen- trics cross all the radii, appearing to form complete circles. (See Fig. 47.) They are divided into Simple and Compound snares. a. A Simple orbweb is simply an orb of radiating straight lines crossed by spiral or looped lines. The snare of the Furrow spi- der (Epeira strix) is a typical example. b. A Compound orbweb adds to the sim- l)le orb a system of netted or retitelarian lines crossed and joined at different angles, and placed above and on either side of the upper Fio. 49. Subdivisions of an orbweb. part of tlic orb, or placed bclow tlic Orb. The snare of the Labyrinth Spider (Epeira labyrinthca) is an example. Sim- ple orbicular snares may be approximately arranged into three groups according as they have the Hub Meshed, Sheeted, or Open. I am not aware that any arrangement, description, or nomenclature of the various parts of the orbweb has ever been attempted apart from the following, which will therefore be found convenient and perhaps tlT Oh suffif^iently comprehensive.^ The orb may be naturally divided into the Central Space, CS, the Spiral Space, SS, and the Foun- dation Space, FS. (See Fig. 49.) The Central Space is included between the centre of the orb and the origin of the Spiral Space. It has three distinct parts, the Hub, the Notched zone, and the Free zone. The Hub is a small circular part immediately surrounding the centre, which is either wholly open, or covered in whole or in part by spinning- work. 1. The Meshed Hub is wholly or partly covered by a series of irregularly shaped meshes, through which one can often trace the continuation of the radii as zigzag lines. In fact, it may be considered as a small rudimentary and irregular orbweb (Fig. 50). Usually it nearly corresponds in size to the
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectspiders, bookyear1889
