madillos, but his fast disappearance
proves that the race is not always to the swift, nor the battle to the
strong.

Among the animals which have discarded their old-fashioned coats of
mail, and have successfully protected themselves against all enemies,
may be mentioned the frogs, newts, and their kinspeople, the reptiles.
These latter, the learned, with their delight in multiplying terms, have
classed as amphibians. During the period when the coal forests were
growing over what we now know as England, there were innumerable
amphibians, and even to-day their petrified footmarks are found in
sandstone. The underside of their chests were covered with large bony
plates, and in some cases the rest of the body was covered with
scale-like bones. Yet, all the newts and frogs of to-day have wisely
discarded the old coats of armour used by their forefathers.

The armadillo has an armour of quite another kind, notwithstanding the
fact that pangolins and armadillos belong to the same great family, and
each eats ants. Their plates of armour, or shields, have nothing at all
to do with the hair, nor do they have anything to do with the
exo-skeleton; they are formed of bone material, which appears in the
true skin in the form of tiny shields, and each shield is itself
covered with a hard plate which grows in the outer skin. The actual
formation of these shields differs largely in the various species of
armadillo.

[Illustration: _American Museum of Natural History, New York_

NAOSAURUS AND DIMETRODON, TWO EXTINCT ARMOUR-BEARERS WHO SHOULD HAVE
BEEN WELL ABLE TO PROTECT THEMSELVES.]

[Illustration: AN ARMOUR-BEARER OF PREHISTORIC TIMES WHOSE SHIELD WAS AN
EFFECTIVE PROTECTION AGAINST ENEMY HORNS.]

It is well to remember that the pangolins and armadillos are the last
survivors of a great and ancient family of armour-bearers. Many of their
remote ancestors have been found in the rocks and hills of South
America, and all of their representatives of to-day are small
animals--the last of a doomed race--creatures of yesterday. The
glyptodon is known to have been more than eleven feet in length, and his
near-kinsman, the chlamydothere, was even larger. He was nearly the size
of our present-day rhinoceros. These extinct giants carried on their
backs huge domes of bony plates, that must have rivalled our much-feared
tanks, of trench war fame. One would think they were invulnerable, yet
the glyptodon and the chlamydothere, with many oth