THE PAST CONDITION OF ORGANIC NATURE

by Thomas H. Huxley




IN the lecture which I delivered last Monday evening, I endeavoured to
sketch in a very brief manner, but as well as the time at my disposal
would permit, the present condition of organic nature, meaning by that
large title simply an indication of the great, broad, and general
principles which are to be discovered by those who look attentively at
the phenomena of organic nature as at present displayed. The general
result of our investigations might be summed up thus: we found that the
multiplicity of the forms of animal life, great as that may be, may be
reduced to a comparatively few primitive plans or types of construction;
that a further study of the development of those different forms
revealed to us that they were again reducible, until we at last brought
the infinite diversity of animal, and even vegetable life, down to the
primordial form of a single cell.

We found that our analysis of the organic world, whether animals or
plants, showed, in the long run, that they might both be reduced into,
and were, in fact, composed of, the same constituents. And we saw that
the plant obtained the materials constituting its substance by a
peculiar combination of matters belonging entirely to the inorganic
world; that, then, the animal was constantly appropriating the
nitrogenous matters of the plant to its own nourishment, and returning
them back to the inorganic world, in what we spoke of as its waste; and
that finally, when the animal ceased to exist, the constituents of its