grey, six-legged creatures about the size of
a small lady-bird, covered with hairs, and possessing two strong forceps
projecting from their heads. They are so formed that they cannot go
forward, but move always backward by a series of jerks. As they live
upon ants and are so strangely formed, they have to resort to stratagem
in order to entrap their prey, and this they do by means of pits formed
in the sand in which they live; into these pits the ants fall, and are
seized by the forceps of the ant-lion, who lies in wait at the bottom.
Many a time have I watched the formation of these pits, and will try to
describe the process. The insect begins describing a small circle on
the surface of the sand by jerking himself backwards and flinging the
sand away with his flat head and closed forceps, which form a kind of
shovel. Each circle is smaller than the last, until the pit is like an
inverted cone, and the ant-lion lies buried at the bottom, only his
forceps being visible. When an ant has fallen headlong down into the pit
it makes frantic efforts to escape, and if the ant-lion sees that it is
likely to get beyond his reach, he then with his forceps flings some
sand at it with such unerring aim the poor victim is sure to roll over
and over until it reaches the jaws of its captor, who feasts upon it and
then flings the remains of the body out of the pit.
One difficulty was how to ensure a supply of ants, but this was overcome
by filling a box with part of an ants' nest, and as these insects
settled down and seemed content with their quarters, they were ready
when wanted, and three times a day the lions had to be fed! One learns
to sacrifice one's feelings in the cause of science, but to the last it
was a real distress to me to have to put the poor little ants where they
would be devoured; but Nature is cruel, and from the real lion to his
insect namesake, preying upon one another seems the prevailing law of
her realm.
As the ant-lions grew, the pits increased in size. At first they were
about as large as a threepenny-piece, but ended by measuring more than
two inches across.
I could not tell whether the insect moulted its skin, as it was always
hidden, but in July, after four months' feeding, the ant-lions changed
into chrysalides, which looked like perfectly round balls of sand.
The box was placed in a warm greenhouse, and in seven weeks' time the
perfect insects appeared. They were like small dragon-flies, with
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