Page 106 - The Miracle in the Spider

106 THE MIRACLE IN THE SPIDER

Useful Legs
The spider has four pairs of legs
enabling it to walk and climb even under
the most difficult conditions. Each leg
consists of seven parts. At the end of each
leg are hairs called "scopula." Thanks to
these the spider is able to walk on walls or
even upside down.
The special construction of spiders'
An enlarged photograph of the
legs does not stop with allowing it to walk sensitive hairs on the spider's legs.
on non-flat surfaces. Despite the fact that
their eyes do not see well, the spiders' ability to move about comfortably
at night is due to the construction of their legs. Some species of spider can
only sense light, or in other words possess only 10 percent of the sight of
a human being. But despite this, spiders spin their webs at night and
move about easily on them at the same time.
Spiders move about without treading on the sticky parts of the web,
only the dry parts. They owe the fact that they are able to escape without
getting caught, on the rare occasions that they tread on the sticky parts, to
the fact that their feet are coated with a special liquid from their glands.
The ends of the combs are known as spinnerets, each of which is covered
with hundreds of spigots. The liquid silk produced by the glands in its
abdomen is pushed out of the body by these nozzles and then spun in the
form of silk.

Superior Sensory Capabilities

With the exception of jumping spiders, most spiders have rather
poor sight, and can only see for short distances. This disability, which
might be a great disadvantage for a hunter, is compensated for by the
spider's particularly sensitive early warning system.
This warning system is based upon the sense of touch. The body is
covered with hairs which are very sensitive to vibration. Each one of these