CONSTRUCTION OF AN ORBWEB. 69 
from one tree to another, or would fly in the air, he first lets himself down 
from the twig he stands on by a web as in Fig. 1, and then, laying hold 
of it with his fore feet, and bearing himself by that, puts out a web as in 
Fig. 2, which is drawn out of his tail with infinite ease in the gentle 
moving air, to what length the spider pleases, and 
if the farther end happens to catch by a shrub 
or the branch of a tree, the spider immediately 
feels it, and fixes the hither end of it to the web 
by which he lets himself down, and goes over by 
that web which he put out of his tail as in Fig. 
3, and this my eyes have innumerable times made 2 
me sure of.” (See Fig. 65.) The habit indeed = 
prevails and is utilized for many func- 
Use of tions; sometimes to secure a convenient é b 
moore attitude for cleansing the limbs and ab- ees a 
domen; sometimes as a position of guard he ;/ > 
or rest when the spider through fright has cast 
itself from its snare or nest, and has paused mid- 
way of the ground; sometimes as a favorable point 
of departure on a ballooning excursion. But most frequently the swinging 
basket serves, as here, when exploiting surroundings for an available orb 
site, and to work in the prime foundation line. While suspended thus she 
keeps one, or yet more frequently both fore legs extended slightly curved 
in the attitude of “on guard,” and either held rigidly or occasionally waved 
to and fro feeling for the indi- 
cations of the presence of the 
friendly trial line, or of un- 
friendly objects. 
This use of the fore legs is 
habitual in all movements of 
spiders from point to 
Fic. 65. Jonathan Edwards’ illus- 
tration. 
ss point. While engaged 
Antenne. !” dragging a founda- 
tion line around vines 
and twigs, over leaves or other 
surfaces, she will often pause and 
wave the extended fore legs as 
though prospecting her way not 
only, but testing the safety of 
her surroundings. ‘The action frequently reminded me of the character- 
istic use of the antenne by ants and other insects; and, indeed, I have 
little doubt the fore legs of spiders do have in part the function of an- 
tenne. (See Fig. 66.) 
* Am. Jour. Sci. and Arts, Vol. XXT., 1832, pages 112, 113. 
Fig. 66. Antennal use of the fore legs. 
