Pol´y-the-ism [Gr. polys, many; theos, god.]

Po-rif´e-ra [Lat. porus, pore; fero, bear.]

Pre-Pa-læ-o-lith´ic [Lat. præ, before; Palæolithic.] The period of time preceding the Ancient Stone Age.

Pri-ma´tes [Lat. primus, first.] An order of mammals.

Pro-bos-cid´e-a [Gr. pro, before; bosko, feed.]

Pro-nu´cle-us [Lat. pro, before; nucleus, kernel.]

Pros-en-ceph´a-lon [Gr. pro, before; enkephalos, brain.] A fundamental segment of the brain.

Pro-to-hip´pus [Gr. protos, first; hippos, horse.]

Pro-toph´y-ta [Gr. protos, first; phyton, plant.]

Pro´to-plasm [Gr. protos, first; plasma, < plasso, form.]