how Spiders effect their aérial Excursions. 457 
on the 2nd of October, and inclosed in glass phials with ground 
stoppers, where they were suffered to remain till the 16th of 
December, an interval of seventy-five days, without either food 
or moisture; yet at the expiration of that period, the only alte- 
rations perceptible in their external condition were a small de- 
crease in bulk, and a slightly wrinkled appearance, particularly 
of the abdomen: but their functions were seemingly unim- 
paired ; for on warm days, or when excited by artificial heat, 
they were lively in their motions, and to the last continued 
to produce their threads, which were often destroyed for the 
purpose of ascertaining whether they would be replaced by 
others with apparently the same facility as at the time of their 
capture. 
It is particularly deserving of notice, that these insects, though 
unable to climb up the smooth perpendicular sides of the phials 
on their first introduction, soon contrived to traverse the interior 
of their prisons in every direction. 
In order to illustrate their manner of proceeding on this occa- 
sion, the case of an individual has been selected for descrip- 
tion,—the same method, with a few trivial modifications, being 
pursued by all. Elevating the abdomen, and pressing the spin- 
ning-apparatus against the side of the phial, this spider emitted 
from its papillæ a little viscous fluid, which on exposure to the 
air hardened into a minute semi-transparent speck ; then moving - 
to a short distance, and drawing out a thread after it, one end of 
which remained fixed to the spot it had just quitted, it connected 
this filament with another part of the phial by applying the 
spinners as before. Several lines being thus produced, the 
spider speedily raising itself upon them above the bottom of the 
" phial, promoted its undertaking by repeating the process just 
described; every step so gained enabling it to carry its opera- 
tions still higher. 
3N2 From 
