Fig. 29.
The web of Nephila plumipes, described by Wilder, consists also of loops running round about quarter of a circle, [Fig. 30]; and in this web the smooth cross-lines which are first spun are not removed, but remain after it is finished. [Fig. 31] shows part of one side of a web; the arrows marking the smooth thread, and the direction in which it was spun.
Fig. 30.
Argiope, the large black and yellow autumn spiders, cross the middle of the web with a zig-zag band of white silk, which, as the web is obliquely hung, partly conceals the spider under it. These spiders also spin each side of the web, and two or three inches from it, a screen of irregular threads of unknown use.
