hy, as
coming from him, of our most respectful attention. "It is plain," we
find him saying, "that before the class of reptiles was introduced upon
our globe, the fishes, being then the only representatives of the type
of vertebrata, were invested with the characters of a higher order,
embodying, as it were, a prospective view of a higher development in
another class, which was introduced as a distinct type only at a later
period; and from that time the reptilian character, which had been so
prominent in the oldest fishes, was gradually reduced, till in more
recent periods, and in the present creation, the fishes lost all this
herpetological relationship, and were at last endowed with characters
which contrast as much, when compared with those of reptiles, as they
agreed closely in the beginning. Lepidosteus alone reminds us in our
time of these old-fashioned characters of the class of fishes as it was
in former days."

[Illustration: Fig. 58

PLEURACANTHUS LAEVISSIMUS.

(_Coal Measures._)

(Half nat. size.)]

The ancient fishes seem to have received their fullest development
during the Carboniferous period. Their number was very great: some of
them attained to an enormous size, and, though the true reptile had
already appeared, they continued to retain, till the close of the
system, the high reptilian character and organization. Nothing, however,
so impresses the observer as the formidable character of the offensive
weapons with which they were furnished, and the amazing strength of
their defensive armature. I need scarce say, that the Palaeontologist
finds no trace in nature of that golden age of the world, of which the
poets delighted to sing, when all creatures lived together in unbroken
peace, and war and bloodshed were unknown. Ever since animal life began
upon our planet, there existed, in all the departments of being,
carnivorous classes, who could not live but by the death of their
neighbors, and who were armed, in consequence, for their destruction,
like the butcher with his axe and knife, and the angler with his hook
and spear. But there were certain periods in the history of the past,
during which these weapons assumed a more formidable aspect than at
others; and never were they more formidable than in the times of the
Coal Measures. The teeth of the Rhizodus--a ganoidal fish of our coal
fields--were more sharp and trenchant than those of the crocodile of the
Nile, and in the larger specimens fully fo