ile and fish, it has to
be admitted that we are dealing from first to last with a human embryo
with peculiarities of its own.

[Illustration: "DARWIN'S POINT" ON HUMAN EAR (MARKED D.P.)

It corresponds to the tip (T) of the ear of an ordinary mammal, as shown
in the hare's ear below. In the young orang the part corresponding to
Darwin's point is still at the tip of the ear.]

[Illustration: _Photo: J. Russell & Sons._

PROFESSOR SIR ARTHUR KEITH, M.D., LL.D., F.R.S.

Conservator of the Museum and Hunterian Professor, Royal College of
Surgeons of England. One of the foremost living anthropologists and a
leading authority on the antiquity of man.]

[Illustration: _After T. H. Huxley (by permission of Messrs.
Macmillan)._

SKELETONS OF THE GIBBON, ORANG, CHIMPANZEE, GORILLA, MAN

Photographically reduced from diagrams of the natural size (except that
of the gibbon, which was twice as large as nature) drawn by Mr.
Waterhouse Hawkins from specimens in the Museum of the Royal College of
Surgeons.]

Every human being begins his or her life as a single cell--a fertilised
egg-cell, a treasure-house of all the ages. For in this living
microcosm, only a small fraction (1/125) of an inch in diameter, there
is condensed--who can imagine how?--all the natural inheritance of man,
all the legacy of his parentage, of his ancestry, of his long pre-human
pedigree. Darwin called the pinhead brain of the ant the most marvellous
atom of matter in the world, but the human ovum is more marvellous
still. It has more possibilities in it than any other thing, yet without
fertilisation it will die. The fertilised ovum divides and redivides;
there results a ball of cells and a sack of cells; gradually division of
labour becomes the rule; there is a laying down of nervous system and
food-canal, muscular system and skeleton, and so proceeds what is
learnedly called differentiation. Out of the apparently simple there
emerges the obviously complex. As Aristotle observed more than two
thousand years ago, in the developing egg of the hen there soon appears
the beating heart! There is nothing like this in the non-living world.
But to return to the developing human embryo, there is formed from and
above the embryonic food-canal a skeletal rod, which is called the
notochord. It thrills the imagination to learn that this is the only
supporting axis that the lower orders of the backboned race possess. The
curious thing is that it does not become th