aid to take leave of the
simial type, and become a true human creature. Even, as we shall
see, the varieties of his race are represented in the progressive
development of an individual of the highest, before we see the
adult Caucasian, the highest point yet attained in the animal
scale.

"To come to particular points of the organization. The brain of
man, which exceeds that of all other animals in complexity of
organization and fulness of development, is, at one early period,
only 'a simple fold of nervous matter, with difficulty
distinguishable into three parts, while a little tail-like
prolongation towards the hinder parts, and which had been the first
to appear, is the only representation of a spinal marrow. Now, in
this state, it perfectly resembles the brain of an adult fish, thus
assuming _in transitu_ the form that in the fish is permanent. In a
short time, however, the structure is become more complex, the
parts more distinct, the spinal marrow better marked; it is now
the brain of a reptile. The change continues; by a singular motion,
certain parts (_corpora quadragemina_), which had hitherto appeared
on the upper surface, now pass towards the lower; the former is
their permanent situation in fishes and reptiles, the latter in
birds and mammalia. This is another advance in the scale, but more
remains yet to be done. The complication of the organ increases;
cavities, termed _ventricles_, are formed, which do not exist in
fishes, reptiles, or birds; curiously organized parts, such as the
corpora striata, are added; it is now the brain of the mammalia.
Its last and final change alone seems wanting,--that which shall
render it the brain of man.'"--pp. 150-152.

Usually, it is true, each species produces only its like,--"every
creeping thing and beast of the earth" bringing forth young "_after his
kind_." But the development of a single animal, under the ordinary law,
takes place in a few weeks or days; while the development of distinct
races and species is the work of a whole creation, and is spread over
countless ages. It is reasonable to suppose, that the latter is effected
by means of a higher law, manifesting itself only at long intervals. Its
infrequent manifestation is no argument against the regularity and
necessity of its occurrence,--against its being a law at all. The com