arked a precipitate when it is mingled with the blood of an
anthropoid ape. But when it is mingled with the blood of an American
monkey there is only a slight clouding after a considerable time and
no actual precipitate. When it is added to the blood of one of the
distantly related "half-monkeys" or lemurs there is no reaction or only
a very weak one. With the blood of mammals off the simian line
altogether there is no reaction at all. Thus, as a distinguished
anthropologist, Professor Schwalbe, has said: "We have in this not only
a proof of the literal blood-relationship between man and apes, but the
degree of relationship with the different main groups of apes can be
determined beyond possibility of mistake." We can imagine how this
modern line of experiment would have delighted Darwin.

[Illustration: THE GORILLA, INHABITING THE FOREST TRACT OF THE GABOON IN
AFRICA

A full-grown individual stands about 5 feet high. The gait is shuffling,
the strength enormous, the diet mainly vegetarian, the temper rather
ferocious.]

Embryological Proof of Man's Relationship with a Simian Stock

In his individual development, man does in some measure climb up his own
genealogical tree. Stages in the development of the body during its nine
months of ante-natal life are closely similar to stages in the
development of the anthropoid embryo. Babies born in times of famine or
siege are sometimes, as it were, imperfectly finished, and sometimes
have what may be described as monkeyish features and ways. A visit to an
institution for the care of children who show arrested, defective, or
disturbed development leaves one sadly impressed with the risk of
slipping down the rungs of the steep ladder of evolution; and even in
adults the occurrence of serious nervous disturbance, such as
"shell-shock," is sometimes marked by relapses to animal ways. It is a
familiar fact that a normal baby reveals the past in its surprising
power of grip, and the careful experiments of Dr. Louis Robinson showed
that an infant three weeks old could support its own weight for over two
minutes, holding on to a horizontal bar. "In many cases no sign of
distress is evinced and no cry uttered, until the grasp begins to give
way." This persistent grasp probably points back to the time when the
baby had to cling to its arboreal mother. The human tail is represented
in the adult by a fusion of four or five vertebrae forming the "coccyx"
at the end of the backbone, an