. 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. HOllIZONTAL SNARES AND UOMICn OUIiS. 169^ horizontal one; and that it is lifted up gradually by attaching lines at various points upon the upper surface and drawing tliem taut, one after another, until the wliole is lifted up into the domed structure represented in Fig. 154. I may add tliat Dr. Marx was also able to collect cocoons of the species, and descriljc the manner in which they are hung in the neigh- borhood of tlie web
. 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. HOllIZONTAL SNARES AND UOMICn OUIiS. 169^ horizontal one; and that it is lifted up gradually by attaching lines at various points upon the upper surface and drawing tliem taut, one after another, until the wliole is lifted up into the domed structure represented in Fig. 154. I may add tliat Dr. Marx was also able to collect cocoons of the species, and descriljc the manner in which they are hung in the neigh- borhood of tlie The manner in which this change is wrought was determined by Dr. Marx, and he has kindly i)laced at my disposal his notes upon the .same. When first observed by him (at A. M.), the snare lay in a horizontal plane, as shown at Fig. 158, and had more than fifty radii. It was hung between the tips of the branches of a bush. At 12 M. the borders of the snare were bent downward, causing it to assume the form of a shallow dome. At 4 P. M. the transformation had so far progressed as to bring the web to the structure represented at Fig. 159. The work was carried on in this wise: At the marginal edges were ^ j outgoing lines, as c b. Fig. 158, used to support or brace the snare, as is usual with hor- J izontal orbs. On Fi<;. 158. Basilica spider's mode of tranHforming a liorizontal into a domed orb. these at certain points (c) were fastened lines (cd), which were attached to a branch (d) some distance below and to one side of the i)lanc. These lines (c d) were gradually borne downward until they sition of the dotted line, a b. This action caused the edges; and by continuing this manipulation foundation lines, the orb was forced first into the shape of a shallow dome flattened at the pole, and then into the form of the ty2)ical web as above described. (Fig. 159.) This action was seen "repeated over a dozen ; But it was manifest that some other method had been b
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectspiders, bookyear1889
