326 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 
spinnerets, not interwoven with them. When a sufficient number has been 
laid upon the original frame, by the repeated spinning and beating action 
of the spider, the whole presents the appearance of a thickened sheet 
wrought into the form of a tube. (Fig. 310.) 
I have observed the overspinning of an under- 
ground burrow by a Purseweb in a glass jar. The 
same method was followed, except that the frame lines 
were spun against the concavity of the 
burrow and the inner surface of the glass. 
The spider then proceeded to thicken 
over the frame by spinning against it lit- 
tle ribbons of silk and beating them down 
with her long spinnerets. When hang- 
ing head downward, with claws clasping 
the frame lines, and spinning upward 
against the roof of her burrow (Fig. 312), 
she presented to the observer a rather 
odd appearance. No doubt this is the 
mode by which the spider silklines the 
2 underground part of her tubular snare 
Fic. 311. Purseweb spider’s nest. View below Which extends beneath the sand some- 
ground, as well as above. The subterranean times as far as above the surface, and is 
terminus is expanded and branched. 
either single, or branched, after the man- 
ner represented in Fig. 311. (See also Fig. 303.) 
The same method of spinning is used by our American tarantula, Eu- 
rypelma hentzii, in weaving the rug upon which it often loves to stay 
when in artificial confinement. In the act of spinning, the 
eae sie long posterior spinnerets are curved upward and forward (which 
A co is, indeed, an habitual position with this tribe), and from the 
spinning tubes along the exterior part of the spinneret are given 
out numerous fine threads. 
These are pressed to the ground 
by the downward motion of 
the spinnerets. The abdomen 
is then lifted up, and by this 
action the threads are drawn 
out. Again the downward mo- 
tion is repeated, and simulta- 3% : > sb = 
neously the end of the abdo- Y, fy YY / WM YJ 
men to which the i innerets Fic. 312. Purseweb spider working the weft on an 
are attached receives a lateral underground frame. 
motion that causes the threads to be spread over the surface of the 
ground. At the same time the animal slowly moves its whole body 
around, as upon a pivot, thus dispersing the silk over a circular patch of 
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