be long-toed corncrakes, living in meadows instead of in swamps; that there
should be woodpeckers where hardly a tree grows; that there should be
diving thrushes and diving Hymenoptera, and petrels with the habits of
auks.

ORGANS OF EXTREME PERFECTION AND COMPLICATION.

To suppose that the eye with all its inimitable contrivances for adjusting
the focus to different distances, for admitting different amounts of light,
and for the correction of spherical and chromatic aberration, could have
been formed by natural selection, seems, I freely confess, absurd in the
highest degree. When it was first said that the sun stood still and the
world turned round, the common sense of mankind declared the doctrine
false; but the old saying of Vox populi, vox Dei, as every philosopher
knows, cannot be trusted in science. Reason tells me, that if numerous
gradations from a simple and imperfect eye to one complex and perfect can
be shown to exist, each grade being useful to its possessor, as is
certainly the case; if further, the eye ever varies and the variations be
inherited, as is likewise certainly the case; and if such variations should
be useful to any animal under changing conditions of life, then the
difficulty of believing that a perfect and complex eye could be formed by
natural selection, though insuperable by our imagination, should not be
considered as subversive of the theory. How a nerve comes to be sensitive
to light, hardly concerns us more than how life itself originated; but I
may remark that, as some of the lowest organisms in which nerves cannot be
detected, are capable of perceiving light, it does not seem impossible that
certain sensitive elements in their sarcode should become aggregated and
developed into nerves, endowed with this special sensibility.

In searching for the gradations through which an organ in any species has