. 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. 220 AMERICAN SPIDERS AND THEIR SPINNINGWORK. structure which is represented at Fig. 206. It is easy to explain the mode of forming tliis remarkable framework, if we suppose that the spider was perched upon the twig, a, and emitted from her spinnerets a thread which was carried out and upward by the wind, and From t^^^P th entangled at b, thus forming the prime foundation line, ab. Thence she could have moved to the point betwee
. 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. 220 AMERICAN SPIDERS AND THEIR SPINNINGWORK. structure which is represented at Fig. 206. It is easy to explain the mode of forming tliis remarkable framework, if we suppose that the spider was perched upon the twig, a, and emitted from her spinnerets a thread which was carried out and upward by the wind, and From t^^^P th entangled at b, thus forming the prime foundation line, ab. Thence she could have moved to the point between d and a, whence she would have dropped to the ground, a distance of ten feet, and hitched a second line to a tuft of grass. A third line might readily have been secured by dropping from the point d, the natural swaying of the spider, increased by a breeze, carrying her to c. This line, dc, could easily have been pulled in by the cross lines above and below the orb. A convenient frame being thus obtained, the spinning of the orb would be a simple mat- / .^viiisa^^a^ to the side shrubbery at c, c, may also liave been made by aid of the breeze in part. If, in the absence of direct observation, one were to deny the use of air currents, then it must be supposed that the spider carried its line along the tree to the tip of the branch, b, which was twenty-five feet above the ground; and after that it would be difficult to conjecture how she could have proceeded. In fact, in this case the " carrying around " theory alluded to in a foregoing chapter appears to me quite incredible. If we admit that the moving breeze materially aided the spider in her work of construction, and that she was thus in part dependent upon chance, yet there remains a pretty wide field for intelligent selection and adaptation. One would suppose that it required a really nimble witted creature to seize an unexpected opportunity like the above and turn it to such good account. Nor is this an excepti
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectspiders, bookyear1889
