r, flesh, when it is to be had. I give my tadpoles small pieces
of beef, but in the ditches where they swarm, animal matter is to be had
in plenty as a rule.

The mouth at this time is a very different structure from that which is
found in the adult frog: it is fringed by a pair of broad fleshy lips
armed with rows of tiny horny teeth--a curious place for teeth; the
mouth itself is furnished with a pair of teeth--also horny--resembling
the beak of a parrot.

[Illustration: Fig. 4.--Tadpole, showing breathing-tube, magnified.]

During this time these tiny little creatures bear a really close
resemblance to the young of many fish. In both young fishes and
tadpoles, for some time after leaving the egg, breathing is done by
means of very delicate branching gills, standing out on each side of the
head. One of these branches, highly magnified, is shown in fig. 3; at C
(fig. 1) the gills are shown in their natural position. If you can
manage to place a tadpole at this stage under the microscope, you will
see the blood, in the shape of little oval discs, coursing through the
blood-vessels of these gills. These breathing organs, however, are a
source of danger, for they are easily injured, so that, in the tadpole,
as in the fish, they are soon replaced by gills enclosed within a little
chamber on each side of the head. Breathing now takes place by drawing
water in at the mouth, passing it through the chambers and over the
gills, and expelling it through a small hole which opens in the form of
a short tube on the left side of the neck (shown in fig. 4), if a neck
can be distinguished in an animal where the head passes insensibly into
the body! But yet another change in the breathing apparatus takes place.
During the time that the gills are being changed, a pair of lungs are
being developed, and the first hint that they are growing is given by
the frequent journeys to the top of the water for the purpose of sucking
in air.

(_Concluded on page 37._)

[Illustration: "Then came the difficult task of bringing down the little
lad."]

LONG TOM'S GRATITUDE.

'You are a silly, you are; fancy wasting a brand-new shilling on a
circus kid!'

'Nonsense!' was the elder boy's answer; 'first you nearly get run over
by dragging her away from the horse's hoofs, and then you go and give
her all your pocket-money--I've no patience with you.'

Secretly, Dick Chilcote admired the plucky action, but he was too proud
to say so. But