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COR UAP A Ein Gays 
CONSTRUCTION OF AN ORBWEB. 
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A pEscripTion of the remaining part of the orb will be better reached 
by a detailed account of the manner in which an orbweb is constructed. 
There are some variations in methods among different species, 
Laying as might be expected from the varieties of webs, but the process 
Out : : ; ; cf 
Frame 'S Substantially the same in all species observed. The first step 
of Snare. is to secure a suitable framework upon which to hang the orb, 
which is known as the Foundation or Frame, and the several 
parts composing it, as Foundation Lines. The spider has two methods of 
accomplishing this. 
First, the frame lines are laid down “by hand.” The spider crawls 
along the objects over and upon which she purposes to spin her snare, 
drawing after her a 
A Frame jine which at various 
Laid : 
Down, Points she fastens to 
the surface in this 
wise: the spinnerets, which are 
grouped in a little rosette at the 
Fic. 58. Epeira moving with dragline and anchorage. end of the abdomen, have a large 
number of minute hollow tubes or spinning spools upon their tips, out 
of which issues a liquid silk of which all spinningwork is formed. The 
spinnerets and their hundreds of spools are moyable at the will of the 
spider. When they are held closely together, the numerous threads emitted 
by them blend into one. When they are held apart, on the contrary, 
various separate threads are formed. As the spider runs along she stops 
here and there, expands her spinning organs, and at the same time 
thrusts them downward and touches the surface. The clustered threads 
thus issued stick to the surface and at once harden, 
Then the spider closes together the spinnerets, as one would close the 
points of his fingers against his thumb, lifts them, moves on, and the con- 
tinuous threads dragged behind her again converge into one 
thread as shown in Fig. 58. An ordinary pocket lens, if applied 
to one of the little white dots which mark the point of adhesion, 
will easily resolve it into various parts and show the above construction. 
At Fig. 59 are magnified drawings of two of these spots. 
(60) 
Drag- 
lines. 
