d care for their
young, seemingly quite inconsistent with the epithet he has applied to
them. In fact, we know so little of the faculties of animals that any
classification based upon our present information about them must be very
imperfect.

Many modifications of Cuvier's great divisions have been attempted. Some
naturalists, for instance, have divided off a part of the Radiates and
Articulates, insisting upon some special features of structure, and
mistaking these for the more important and general characteristics of
their respective plans. All subsequent investigations of such would-be
improvements show them to be retrograde movements, only proving more
clearly that Cuvier detected in his four plans all the great structural
ideas on which the vast variety of animals is founded. This result is of
greater importance than may at first appear. Upon it depends the question,
whether all such classifications represent merely individual impressions
and opinions of men, or whether there is really something in Nature that
presses upon us certain divisions among animals, certain affinities,
certain limitations, founded upon essential principles of organization.
Are our systems the inventions of naturalists, or only their reading of
the Book of Nature? and can that book have more than one reading? If these
classifications are not mere inventions, if they are not an attempt to
classify for our own convenience the objects we study, then they are
thoughts which, whether we detect them or not, are expressed in
Nature,--then Nature is the work of thought, the production of
intelligence carried out according to plan, therefore premeditated,--and
in our study of natural objects we are approaching the thoughts of the
Creator, reading His conceptions, interpreting a system that is His and
not ours.

All the divergence from the simplicity and grandeur of this division of
the animal kingdom arises from an inability to distinguish between a plan
and the execution, of a plan. We allow the details to shut out the plan
itself, which exists quite independent of special forms. I hope we shall
find a meaning in all these plans that will prove them to be the parts of
one great conception and the work of one Mind.

II.

Proceeding upon the view that there is a close analogy between the way in
which every individual student penetrates into Nature and the progress of
science as a whole in the history of humanity, I continue my sketch of the
s