It is very interesting to think of the numerous types of locomotion
which animals have discovered--pulling and punting, sculling and rowing,
and of the changes that are rung on these four main methods. How
striking is the case of the frilled lizard (Chlamydosaurus) of
Australia, which at the present time is, as it were, experimenting in
bipedal progression--always a rather eventful thing to do. It gets up on
its hind-legs and runs totteringly for a few feet, just like a baby
learning to walk.
How beautiful is the adventure which has led our dipper or
water-ouzel--a bird allied to the wrens--to try walking and flying under
water! How admirable is the volplaning of numerous parachutists--"flying
fish," "flying frog," "flying dragon," "flying phalanger," "flying
squirrel," and more besides, which take great leaps through the air. For
are these not the splendid failures that might have succeeded in
starting new modes of flight?
Most daring of all, perhaps, are the aerial journeys undertaken by many
small spiders. On a breezy morning, especially in the autumn, they mount
on gate-posts and palings and herbage, and, standing with their head to
the wind, pay out three or four long threads of silk. When the wind tugs
at these threads, the spinners let go, and are borne, usually back
downwards, on the wings of the wind from one parish to another. It is
said that if the wind falls they can unfurl more sail, or furl if it
rises. In any case, these wingless creatures make aerial journeys. When
tens of thousands of the used threads sink to earth, there is a "shower
of gossamer." On his _Beagle_ voyage Darwin observed that vast numbers
of small gossamer spiders were borne on to the ship when it was sixty
miles distant from the land.
[Illustration: THE AUSTRALIAN FRILLED LIZARD, WHICH IS AT PRESENT TRYING
TO BECOME A BIPED
When it gets up on its hind-legs and runs for a short distance it folds
its big collar round its neck.]
[Illustration: A CARPET OF GOSSAMER
The silken threads used by thousands of gossamer spiders in their
migrations are here seen entangled in the grass, forming what is called
a shower of gossamer. At the edge of the grass the gossamer forms a
curtain, floating out and looking extraordinarily like waves breaking on
a seashore.]
[Illustration: THE WATER-SPIDER
The spider is seen just leaving its diving-bell to ascend to the surface
to capture air.