s more from that of the Gorilla than
the thumb of the Gorilla differs from that of Man, not only by its
shortness, but by the absence of any special long flexor muscle. The
carpus of the Orang, like that of most lower apes, contains nine bones,
while in the Gorilla, as in Man and the Chimpanzee, there are only
eight.

The Orang's foot (Figure 19) is still more aberrant; its very long
toes and short tarsus, short great toe, short and raised heel, great
obliquity of articulation in the leg, and absence of a long flexor
tendon to the great toe, separating it far more widely from the foot of
the Gorilla than the latter is separated from that of Man.

But, in some of the lower apes, the hand and foot diverge still more
from those of the Gorilla, than they do in the Orang. The thumb ceases
to be opposable in the American monkeys; is reduced to a mere rudiment
covered by the skin in the Spider Monkey; and is directed forwards and
armed with a curved claw like the other digits, in the Marmosets--so
that, in all these cases, there can be no doubt but that the hand is
more different from that of the Gorilla than the Gorilla's hand is from
Man's.

And as to the foot, the great toe of the Marmoset is still more
insignificant in proportion than that of the Orang--while in the Lemurs
it is very large, and as completely thumb-like and opposable as in
the Gorilla--but in these animals the second toe is often irregularly
modified, and in some species the two principal bones of the tarsus,
the 'astragalus' and the 'os calcis', are so immensely elongated as to
render the foot, so far, totally unlike that of any other mammal.

So with regard to the muscles. The short flexor of the toes of the
Gorilla differs from that of Man by the circumstance that one slip of
the muscle is attached, not to the heel bone, but to the tendons of the
long flexors. The lower Apes depart from the Gorilla by an exaggeration
of the same character, two, three, or more, slips becoming fixed to the
long flexor tendons--or by a multiplication of the slips.--Again, the
Gorilla differs slightly from Man in the mode of interlacing of the long
flexor tendons: and the lower apes differ from the Gorilla in exhibiting
yet other, sometimes very complex, arrangements of the same parts, and
occasionally in the absence of the accessory fleshy bundle.

Throughout all these modifications it must be recollected that the
foot loses no one of its essential characters. Every Mo