Fear-inspiring is the appearance of the great crab-spider--the Mygale
avicularia, one genus of the formidable Arachnida family--with a body
two inches in length, and, when the legs are expanded, seven inches
across, covered entirely with coarse grey, reddish hairs. It lives
among the rocks in the drier regions; some dwell under stones, others
form artistic tunnels under the earth, and some build their dens in the
thatch of houses. Bates one day saw some Indian children with one of
these monsters secured by a cord round its waist, by which they were
leading it about the house as they would a dog. The hairs with which it
is covered come off when touched, and cause a peculiar and almost
maddening irritation. This is, however, probably owing to their being
short and hard, and thus getting into the fine creases of the skin, and
not to any poisonous quality residing in the hairs. These monstrous
spiders prey on lizards, small birds, and other diminutive vertebrates.
Their muscular power is very great. When the creature is about to seize
its prey, it fixes its hind-feet firmly in the ground, and lifting up
the front ones, darts them forward, and fastens them with the double
hooks which terminate its feet between the cranium and the first
vertebra, thus preventing the possibility of their escaping. Nothing
will then tear it from its prey. When pressed by hunger, it climbs at
night the trees and shrubs in which humming-birds and other small birds
are perched, or have built their nests, and springing on them, grasps
them with its powerful claws. It seizes the anolis, a kind of
water-lizard, in the same way. The fact of its seizing on birds, so
long doubted, though asserted by Madame Marian, the French naturalist,
has been corroborated by Monsieur Jonnes, her countryman. He states
that it spins no web to serve it as a dwelling, but burrows and lies in
ambush in the cliffs and hollow ravines. It often travels to a
considerable distance, and conceals itself under leaves, thence to dart
out on its prey; or it climbs along the branches of trees to surprise
the humming-birds and other small tree-creepers. Bates still further
settles the point.
With regard to the habits of another species which does spin a web, he
says that, catching sight of one of these spiders, he was attracted by
its movements. It was in the crevices of a tree, across which was
stretched a dense web. The lower portion of the web was broken, and two
small birds,--finches,--were entangled in the pieces. They were the
size of the English linnet, and probably male and female. One was quite
dead, the other lay dying under the body of the spider, and was smeared
with the filthy liquor or saliva exuded by the monster.
The mygale carries its eggs enclosed in a cocoon of white silk of a very
close tissue, formed of two round pieces uniting at their borders. It
supports this cocoon under its corselet by means of its antennulae, and
transports it along with itself. When hard-pressed by its enemies, it
abandons it for a time, but returns to take it up as soon as the combat
is concluded. Nearly two thousand eggs are contained in these cocoons.
The young ones when they appear are entirely white, gradually assuming
the colour of the adult.
The falces, or reaping-hook claws, of the great crab-spider are of
enormous size, and ai-e sometimes set in gold and used as toothpicks,
from the idea that they possess some medicinal virtue to cure the
toothache.
The different species vary very much in their habits. One big fellow--
the Mygale Blondii--forms a broad slanting gallery about two feet in
length, the sides of which he lines beautifully with silk. Just before
sunset he may be seen keeping watch near the mouth of his tunnel,
disappearing suddenly when he hears a heavy foot-tread near his
hiding-place.
Many are of the most showy colours. Some double themselves up at the
base of leaf-stalks, so as to resemble a flower, and thus deceive the
insects on which they prey. One of the most extraordinary in
appearance--the Arosoma arcuatum--has two curved, bronze-coloured
spines, an inch and a half in length, proceeding from its abdomen. It
spins a large web, those huge spikes apparently being no impediment to
its work.