al element which is the basis of every individual of
the group."[50] Dr. Morton's definition of species as "primordial
organic forms," agrees with that given by Professor Dana; and both agree
with the Bible, which says that God created plants and animals each
after its kind. A primordial form is a form which was not evolved out of
some other form, but which began to be in the form--subject to such
varieties as we see in the dog, horse, and man--in which it continued
during the whole period of its existence.

The criteria of these primordial forms or species of nature, are, (1.)
Morphological. Animals, however, may approach very nearly in their
structure, and yet belong to different species. It is only when the
peculiarities of structure are indicative of specialty of design, that
they form a safe ground of classification. If the teeth of one animal
are formed to fit it to feed on flesh, and those of another to fit it to
feed on plants; if one has webbed feet and another not; then, in all
such cases, difference of structure proves difference of kind. (2.)
Physiological; that is, the internal nature, indicated by habits and
instincts, furnishes another safe criterion. (3.) Permanent fecundity.
The progenitors of the same species reproduce their kind from generation
to generation; the progeny of different species, although nearly allied,
do not. It is a fixed law of nature that species never can be
annihilated, except by all the individuals included in them dying out;
and that new species cannot be produced. Every true species is
primordial. It is this fact, that is, that no variety, with the
essential characteristics of species, has ever been produced, that
forces, as we saw above, Professor Huxley to pronounce Mr. Darwin's
doctrine to be an unproved hypothesis. Species continue; varieties, if
let alone, always revert to the normal type. It requires the skill and
constant attention of man to keep them distinct.

Now that there are such forms in nature, is proved not only from the
testimony of the great body of the most distinguished naturalists, but
by all the facts in the case.

First, the fact that such species are known to have existed unchanged,
through what geologists consider almost immeasurable periods of time.
Palaeontologists tell us that Trilobites abounded from the primordial age
down to the Carboniferous period, that is, as they suppose, through
millions of years. More wonderful still, the little animals who