EATING AND BITING.
The spiders are best known and hated as animals that bite. The biting
apparatus is shown in Fig. 14, which represents the head and mandibles
of _Epeira vulgaris_, seen from in front. When not in use, the claw is
closed up against the mandible between the rows of teeth; but, when the
jaws are opened to bite, the claws are turned outward, so that their
points can be stuck into any thing between the jaws. Fig. 15 is the
claw still more enlarged, showing a little hole near the point at _a_,
out of which is discharged the secretion of a gland in the head, Fig.
5, _n_. The ordinary use of the mandibles is for killing and crushing
insects, so that the soft parts can be eaten by the spider; and in this
they are aided by the maxillæ, Fig. 1, E. They will sometimes chew an
insect for hours, until it becomes a round lump of skin, with all the
blood sucked out of it; this is then thrown away, the spider swallowing
only such bits as may happen to be sucked in with the liquid portion.
[Illustration: Fig. 14.]
[Illustration: Fig. 15.]
If let alone, no spiders bite any thing except insects useful for food;
but, when attacked and cornered, all species open their jaws, and
bite if they can; their ability to do so depending on their size, and
the strength of their jaws. Notwithstanding the number of stings and
pimples that are laid to spiders, undoubted cases of their biting the
human skin are very rare; and the stories of death, insanity, and
lameness from spider-bites, are probably all untrue.
Many experiments have been tried to test the effect of the bites
of spiders on animals. Doleschall shut up small birds with _Mygale
Javanica_ and _Mygale Sumatrensis_, both large and strong spiders; and
the birds died in a few seconds after being bitten. One of the spiders
was left for ten days without food, and then made to bite another bird,
which was injured, but in six hours recovered. The same author was
bitten in the finger by a jumping spider. The pain was severe for a few
minutes, and was followed by lameness of the finger, and gradually of
the hand and arm, which soon went away entirely.
Bertkau allowed spiders to bite his hand. On the ends of the fingers
the skin was too thick; but between the fingers they easily pricked
it. The bite swelled and smarted for a quarter of an hour, and then
itched for some time, and for a day after itched whenever rubbed, as
mosquito-bites will. He also experimented on flies, which died in a few
minutes after being bitten.
Mr. Blackwall, to test the poison of spiders, made several large ones
bite his hand and arm, and at the same time pricked himself with a
needle. Although the spiders bit deep enough to draw blood, the effect
of their bite was exactly like that of the prick of the needle. No
inflammation or pain followed, and both healed immediately.
Several spiders were placed together, and made to bite one another. The
bitten ones lived always some hours, and died from loss of blood; and
one spider, that had been bitten in the abdomen so that some of the
liver escaped and dried on the outside, lived over a year, apparently
in good health.
A large spider was made to bite a wasp near the base of the right
front-wing, so as to disable it; but it lived thirteen hours.
A bee was bitten by a large spider, but lived three days.
A grasshopper was bitten, and held in the jaws of a spider for several
seconds; but it lived in apparent health for two days.
Insects of the same kinds were wounded in the same places with needles,
and died in about the same time as when bitten.
From these experiments Mr. Blackwall was led to believe that the
secretion from the spider’s jaws is not poisonous, but that insects
die, when bitten, from loss of blood and mechanical injury.
Mr. Moggridge, who studied the habits of trap-door spiders for several
years, was more than once bitten by them, but never had any pain or
inflammation from the bites.
The bites of _Latrodectus guttatus_ of the south of Europe, and an
allied species in California, are much dreaded, but probably as much on
account of the size and conspicuous colors of the spider as any thing
else.
The Tarantula, also a south European spider, has been supposed to
cause epilepsy by its bites, which could only be relieved by music of
particular kinds. These stories appear, however, to be all nonsense: at
any rate, the Tarantula bites produce no such effect nowadays. These
spiders live in holes in sand, out of which they rush after passing
insects, and may be caught by a straw moved carefully over the holes
like an insect. They are no more savage in their habits than other
spiders; and Dufour kept one that soon learned to take flies from his
fingers without biting him.
Spiders of very different species soon learn to take food from the hand
or a pair of forceps, or water from a brush, and will come to the mouth
of their bottle, and reach after it on tiptoe.
Many stories are told of spiders coming out of their holes to listen to
music, and of their being taught to come out and take food at the sound
of an instrument.