, macacus, magots, &c.)
degeneration has not proceeded so far, and the ears are voluntarily
moveable.
[Illustration: FIG. 11.--Rudimentary, or vestigial and useless,
muscles of the human ear. (From _Gray's Anatomy_.)]
(2) _Panniculus carnosis._--A large number of the mammalia are able to
move their skin by means of sub-cutaneous muscle--as we see, for
instance, in a horse, when thus protecting himself against the sucking
of flies. We, in common with the Quadrumana, possess an active remnant
of such a muscle in the skin of the forehead, whereby we draw up the
eyebrows; but we are no longer able to use other considerable remnants
of it, in the scalp and elsewhere,--or, more correctly, it is rarely
that we meet with persons who can. But most of the Quadrumana (including
the anthropoids) are still able to do so. There are also many other
vestigial muscles, which occur only in a small percentage of human
beings, but which, when they do occur, present unmistakeable homologies
with normal muscles in some of the Quadrumana and still lower
animals[5].
[5] See especially Mr. John Wood's papers, _Proc. R. S._, xiii to
xvi, and xviii; also _Journ. Anat._, i and iii. In this connexion
Darwin refers to M. Richard, _Annls. d. Sc. Nat. Zoolg._, tom.
xviii, p. 13, 1852.
(3) _Feet._--It is observable that in the infant the feet have a strong
deflection inwards, so that the soles in considerable measure face one
another. This peculiarity, which is even more marked in the embryo than
in the infant (see p. 153), and which becomes gradually less and less
conspicuous even before the child begins to walk, appears to me a highly
suggestive peculiarity. For it plainly refers to the condition of
things in the Quadrumana, seeing that in all these animals the feet are
similarly curved inwards, to facilitate the grasping of branches. And
even when walking on the ground apes and monkeys employ to a great
extent the outside edges of their feet, as does also a child when
learning to walk. The feet of a young child are also extraordinarily
mobile in all directions, as are those of apes. In order to show these
points, I here introduce comparative drawings of a young ape and the
portrait of a young male child. These drawings, moreover, serve at the
same time to illustrate two other vestigial characters, which have
often been previously noticed with regard to the infant's foot. I allude
to the incurved form of the legs, and
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