the
Darwinian theory, has to a considerable extent been satisfied.

To what extent have the results of this vast activity fulfilled the
expectations of the workers who have achieved them? The Darwin centenary
is a fitting moment at which to take stock of our position. In this
inquiry we shall leave out of consideration the immense and intensely
interesting additions to our knowledge of Natural History. These may be
said to constitute a capital fund upon which philosophers, poets and
men of science will draw for many generations. The interest of Natural
History existed long before Darwinian evolution was thought of and
will endure without any reference to philosophic speculations. She is
a mistress in whose face are beauties and in whose arms are delights
elsewhere unattainable. She is and always has been pursued for her own
sake without any reference to philosophy, science, or utility.

Darwin's own views of the bearing of the facts of embryology upon
questions of wide scientific interest are perfectly clear. He writes
("Origin" (6th edition), page 395.):

"On the other hand it is highly probable that with many animals the
embryonic or larval stages show us, more or less completely, the
condition of the progenitor of the whole group in its adult state. In
the great class of the Crustacea, forms wonderfully distinct from each
other, namely, suctorial parasites, cirripedes, entomostraca, and even
the malacostraca, appear at first as larvae under the nauplius-form; and
as these larvae live and feed in the open sea, and are not adapted for
any peculiar habits of life, and from other reasons assigned by Fritz
Muller, it is probable that at some very remote period an independent
adult animal, resembling the Nauplius, existed, and subsequently
produced, along several divergent lines of descent, the above-named
great Crustacean groups. So again it is probable, from what we know of
the embryos of mammals, birds, fishes, and reptiles, that these animals
are the modified descendants of some ancient progenitor, which was
furnished in its adult state with branchiae, a swim-bladder, four
fin-like limbs, and a long tail, all fitted for an aquatic life.

"As all the organic beings, extinct and recent, which have ever lived,
can be arranged within a few great classes; and as all within each
class have, according to our theory, been connected together by fine
gradations, the best, and, if our collections were nearly perfect, the
onl