dern
periods; each new race being more fully developed than the most perfect
of the preceding era.

Of the truth of the last-mentioned geological theory, Lamarck seems to
have been fully persuaded; and he also shows that he was deeply
impressed with a belief prevalent amongst the older naturalists, that
the primeval ocean invested the whole planet long after it became the
habitation of living beings; and thus he was inclined to assert the
priority of the types of marine animals to those of the terrestrial, so
as to fancy, for example, that the testacea of the ocean existed first,
until some of them, by gradual evolution, were _improved_ into those
inhabiting the land.

These speculative views had already been, in a great degree, anticipated
by Demaillet in his Telliamed, and by several modern writers; so that
the tables were completely turned on the philosophers of antiquity, with
whom it was a received maxim, that created things were always most
perfect when they came first from the hands of their Maker; and that
there was a tendency to progressive deterioration in sublunary things
when left to themselves--

----omnia fatis
In pejus ruere, ac retro sublapsa referri.

So deeply was the faith of the ancient schools of philosophy imbued with
this doctrine, that, to check this universal proneness to degeneracy,
nothing less than the reintervention of the Deity was thought adequate;
and it was held, that thereby the order, excellence, and pristine energy
of the moral and physical world had been repeatedly restored.

But when the possibility of the indefinite modification of individuals
descending from common parents was once assumed, as also the geological
inference respecting the progressive development of organic life, it was
natural that the ancient dogma should be rejected, or rather reversed,
and that the most simple and imperfect forms and faculties should be
conceived to have been the originals whence all others were developed.
Accordingly, in conformity to these views, inert matter was supposed to
have been first endowed with life; until, in the course of ages,
sensation was superadded to mere vitality: sight, hearing, and the
other senses were afterwards acquired; then instinct and the mental
faculties; until, finally, by virtue of the tendency of things to
_progressive improvement_, the irrational was developed in the rational.

The reader, however, will immediately perceive that when all the