On The Origin of Species by Charles Darwin Chapter 16 Page 35

parts of animals. The cells secreting it are called PIGMENT-CELLS.

PINNATE. — Bearing leaflets on each side of a central stalk.

PISTILS. — The female organs of a flower, which occupy a position in the centre of the other floral organs.

The pistil is generally divisible into the ovary or germen, the style and the stigma.

PLACENTALIA, PLACENTATA. — or PLACENTAL MAMMALS, See MAMMALIA.

PLANTIGRADES. — Quadrupeds which walk upon the whole sole of the foot, like the bears.

PLASTIC. — Readily capable of change.

PLEISTOCENE PERIOD. — The latest portion of the Tertiary epoch.