180 
SOME NOTES ON SPIDERS 
In fig. Ill we see the foot greatly magnified of the spider 
in fig. II. The thick bunch of hair called the scopula is said 
to give out a sticky fluid enabling a jumping spider to walk on 
glass or polished surfaces and prevent it falling after a spring 
should it alight on a polished surface. Jumping spiders can 
also open their spinnerets and attach a silk thread to the spot 
from where they spring ; and should they miss their prey they 
climb up these anchor threads, by means of the comb -like 
claws, to await another chance. 
The web-making spider spins a beautiful web of pure silk 
composed of adhesive and non-adhesive threads, the adhesive 
threads being covered with a sticky secretion which adhere to 
any insect that comes in contact with the web. 
Jumping spiders do not spin a web to catch insects 
but hunt insects and stalk them, finally pouncing upon 
them. 
Spiders live by sucking the juices of their prey, drawing 
the juice into the stomach by an apparatus at the end of the 
gullet. 
Eig. IV shows the formidable falces of the spider in fig. I 
greatly magnified ; these falces are perforated to allow the 
poison from the poison-gland to flow through into the body of 
its victim, which is held fast in the claw-like joints. 
There are many other interesting features well worth 
studying in a common spider, such as the means by which 
they breathe air through lung sacs and also air tubes similar 
to the tracheal tubes of insects ; and the spinnerets with 
which they spin webs, form nests, and make silk ropes to let 
themselves drop in an instant to the ground and evade an 
enemy or swing from one place to another. 
The hairs with which the abdomen of the spider in fig. II 
was covered were nearly all lost in the process of mounting it 
as a microscopical slide. However, sufficient remain to 
show that some were branched and others resemble in shape the 
scales of a butterfly. 
