d with spines, or bristles.

In the Mole Cricket (fig. 1) the fore-legs are very strong, being short
and broad, and ending in a broad comb-like plate, which is used for
digging. They are very like the great digging paws of the mole.

The exact way in which insects walk is not easy to describe, and much
study has been given to this most puzzling subject. Many devices have
been adopted to make the insect draw a map of its course. In one
instance the legs of a slow-walking beetle were painted, and the insect
was then made to walk upon a clean sheet of paper; the track made by
each leg being distinguished by the use of a different colour.

From this and other experiments it appears that there are always three
legs in motion at the same time, or nearly so; meanwhile the remaining
three legs support the body. First (as in fig. 2) the left fore-leg
steps out, then the right middle-leg and the left hind-leg. Then the
movement is taken up by the legs of the opposite side of the body, and
so on.

If the movement of the legs in the six-legged insects is difficult to
find out, what shall we say when the centipede (fig. 3) and millipede
come to be examined? These, though not insects, are nearly related to
the insects, and since they are common in our gardens, must be referred
to here.

[Illustration: Fig. 1.--Mole Cricket (magnified).]

According to the lines of a humorous poem, the centipede was said to
have been--

'Happy till
One day a toad, in fun,
Said, "Pray which leg moves after which?"
This raised her doubts to such a pitch
She fell exhausted in the ditch,
Not knowing how to run.'

[Illustration: Fig. 2.--Beetle walking.]

The last pair of legs in the centipede and millipede are never used for
walking, and are generally much longer than the rest. In a South
American species they are provided with delicate nerves, and are used as
antennae or 'feelers,' so that the animal is armed with organs of touch
at each end of the body! In one kind of millipede, in the male the last
pair of legs has a sound-producing apparatus, consisting of a ridged
plate, which, by being rubbed against a set of tiny, bead-like bodies
set in the surface of the last shield covering the body, produces a
peculiar noise.

[Illustration: Fig. 3.--Centipede (magnified).]

Centipedes and millipedes generally shun the light, and hide under
stones and in crevices during the day. But there are some which