s which spring from the middle of the forehead and bend down
in front of the mouth; with these weapons the _Corethra_ larva seizes
its prey and crushes it between two rows of sharp spikes placed under
the mouth; after being bruised and mangled by this apparatus the prey
is ready to be swallowed.

[Illustration: CORETHRA LARVA, MAGNIFIED.]

"But what," asked Jack, "are those four curious black bodies; one pair
near the head, the other pair near the tail of the animal?" They are
air-sacs, and are connected with the breathing or respiration of the
larvae. Some have supposed that they serve the same office as the
swimming bladder of certain fish, which being compressed or dilated at
will enables the creature to remain still in mid-water or to rise or
sink in it. After a time the larva changes to a pupa, in which state
it lives without eating for a few days, and then turns into a gnat. We
now proceed on our walk and come to a part of the road which has a
plantation on either side; we see a little active creature crossing
the road and at once recognise a weasel. Let us keep quite still and
silent, and we shall, I dare say, have an opportunity of watching it
for a short time. Just look at him! how nimbly the little creature
runs along; now he stops and raises his head as if listening for
something, now off he starts again; he is evidently hunting, and
probably is on the scent of a young rabbit, rat, or field-mouse. Ah!
see he has caught something on the grass near the hedge; what has he
got in his mouth? it is a small rat, I think; now he throws his
flexible body over it and gives it one or two bites. Now, Jack, run up
and catch him. Ah! he is off like a shot; you must not think to "catch
a weasel asleep." I often see these little animals in my rambles, and
always stop to witness their extraordinary activity. Weasels will
sometimes climb trees and surprise some unfortunate bird on her nest;
they are fond of eggs, and a bird's young brood are very dainty
morsels; they will also eat moles and are sometimes caught in
mole-traps. An excellent observer mentions a case of a mole-trap
having been found many years ago with two weasels in it; they had been
hunting in the mole's runs, had come in opposite directions, and "by a
curious coincidence, must have both sprung the trap at the same
instant." Weasels are generally classed as vermin and killed on all
possible occasions; I think it is often a mistake to destroy them; no
doubt the