The Mandrill presents a middle condition, the arms and legs being nearly
equal in length, and both being shorter than the spinal column; while
hand and foot have nearly the same proportions to one another and to
the spine, as in Man.

In the Spider monkey ('Ateles') the leg is longer than the spine, and
the arm than the leg; and, finally, in that remarkable Lemurine form,
the Indri ('Lichanotus'), the leg is about as long as the spinal
column, while the arm is not more than 11/18 of its length; the hand
having rather less and the foot rather more, than one-third the length
of the spinal column.

These examples might be greatly multiplied, but they suffice to show
that, in whatever proportion of its limbs the Gorilla differs from Man,
the other Apes depart still more widely from the Gorilla and that,
consequently, such differences of proportion can have no ordinal value.

We may next consider the differences presented by the trunk, consisting
of the vertebral column, or backbone, and the ribs and pelvis, or bony
hip-basin, which are connected with it, in Man and in the Gorilla
respectively.

In Man, in consequence partly of the disposition of the articular
surfaces of the vertebrae, and largely of the elastic tension of some
of the fibrous bands, or ligaments, which connect these vertebrae
together, the spinal column, as a whole, has an elegant S-like
curvature, being convex forwards in the neck, concave in the back,
convex in the loins, or lumbar region, and concave again in the sacral
region; an arrangement which gives much elasticity to the whole
backbone, and diminishes the jar communicated to the spine, and through