82 Life and Intumortality. 
the legs show signs of strengthening, and she is able to 
draw them gradually towards her. A few up-and-down 
movements, and she manages to get into the web again. 
That which, more than anything else, discriminates spiders 
from other animals is their habit of spinning webs. Some 
of the mites spin irregular threads upon plants, or cocoons 
for their eggs, and many insects cocoons in which to 
undergo their changes from larva to imago, but in the 
spiders the spinning-organs are much more complicated, 
and used for a greater variety of purposes, for making 
egg-cocoons, silk linings to their nests, and nets for catching 
insects. The spider’s thread differs from that of insects, in 
being constituted of a great number of finer threads laid 
together, while soft enough to coalesce into one. Each 
spinneret is provided with a number of little tubes, which 
convey the viscid liquid that forms the thread from glands 
in the spider’s body. In Agalena the two hinder spinnerets 
are long, and have spinning-tubes along the under side of the 
last joint. 
When about to produce a thread the spider presses the 
spinnerets against some object and forces out from each 
tube enough of the secretion to adhere to it, when the spin- 
nerets are moved away, drawing the viscid liquid out, which 
hardens at once into threads for each tube. A band of 
threads is formed when the spinnerets are kept apart, 
but when closed together the fine threads unite into one 
or more large ones. Commonly the spinning is aided by 
the hinder feet, which guide the thread, keeping it clear of 
surrounding objects, and even pulling it from the spin- 
nerets. 
Spiders are best known and hated as animals that bite. 
Their biting-apparatus, the mandibles, are located in front of 
the head. Partly in the basal joints of these organs and 
partly in the head, the poison-glands are seated, from which 
is discharged through a tube the venom, which makes spi- 
ders so much to be feared. This tube opens at the point of 
