Morphology. a 
retain in a dwindled and useless condition (Fig. 11). 
This is likewise the case in anthropoid apes; but in 
not a few other Quadrumana (e.g. baboons, macacus, 
magots, &c.) degeneration has not proceeded so far, 
and the ears are voluntarily moveable. 
(2) Panniculus carnosis—A large number of the 
mammalia are able to move their skin by means of 
sub-cutaneous muscle—as we sce, for instance, in a 
“horse, when thus protecting himself against the 
sucking of flies. We, in common with the Quad- 
rumana, 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 Quad- 
rumana and still lower animals '. 
(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 sugges- 
tive peculiarity. For it plainly refers to the condition 
1 See especially Mr. John Wood’s papers, Proc. R. S., xiii to xvi, and 
xviii; also Journ Anat.,i and iti, In this connexion Darwin refers 
to M. Richaid, das. d. Sc. Nat. Zoolg., tom. xviii, p. 13, 1852. 
