n the order presented by existing organic
remains. While covered by the sea, what now form Europe and America
could only be peopled by marine animals; but as the land rose or the
waters subsided into their ocean channels, and dry land appeared,
reptiles and amphibiae might become the occupants; next, as the earth
became drier and more salubrious, the new continent would be resorted to
by terrestrial animals; in a still more advanced stage of purification
and salubrity, man himself, as the lord of all the preceding classes of
immigrants, would take possession, and as he still continues the living
occupant it is premature to look for his petrifaction.

ORIGIN OF THE ANIMATED TRIBES.

Science has mastered many perplexities, but is almost powerless as ever
in generation. All that lives, and still more all that moves, must have
a pre-existing germ formed independently of the created being, but which
is essential to its existence, and fixes the type of organization. The
old adage--_omne animal ab ovo_--may be taken as generally true. But
though every animal has its primordial egg or germ, all germs are not
identical. In the beginning of life there are other organic elements
besides the ovum. Partly on direct proof and partly on good analogy, it
may be inferred that these differ in different species--that each in the
first stages of existence is bound by a different and immutable mode of
development--and, if so, there can be no embryotic identity. "By no
change of conditions," says Dr. CLARKE, "can two ova of animals of the
same species be developed into different animal species; neither by any
provision of identical conditions can two ova of different species be
developed into animals of the same kind." If these views be right, and
we believe them to be so, there cannot be a transmutation of species
under the influence of external circumstances.

Baffled in the effort either to create species or organically to change
them, attempts have been made to approach nearer to the source of
vitality, and explain the chemical, electric, or mechanical laws by
which the vital principle is influenced. For this purpose various
hypotheses have been put forth; one is the noted conjecture of Lord
MONBODDO, that man is only an advanced development of the chimpanzee or
ourang-outang. A second explanation is that given by LAMARCK, who
surmised, and with much ingenuity attempted to prove, that one being
advanced in the course of generations i