PAN´CRE-AS (Gr. [Greek: pas], [Greek: pantos], _pas_, _pantos_, all, and [Greek: kreas], _kreas_, flesh). A long, flat gland situated near the stomach; in the lower animals the analogous organ is called the sweet-bread. PA-PIL´LÆ (L. _papil´la_). The minute prominences in which terminate the ultimate fibres of the nerves of touch and taste. PA-RAL´Y-SIS. A disease of the nervous system marked by the loss of sensation, or voluntary motion, or both; palsy. PAR-A-PLE´GI-A (Gr. [Greek: paraplêssô], _paraplesso_, to strike amiss). A form of paralysis affecting the lower half of the body. PA-TEL´LA (L. dim. of _pat´ina_, a pan). The knee-pan; a small bone. PEL´VIS (L.). Literally a basin; the bony cavity at the lower part of the trunk. PEP´SIN (Gr. [Greek: peptô], _pepto_, to digest). The organic principle of the gastric juice. PER-I-STAL´TIC MOVE´MENTS (Gr. [Greek: peristellô], _peristello_, to contract). The slow, wave-like movements of the stomach and intestines. PER-I-TO-NE´UM (Gr. [Greek: periteinô], _periteino_, to stretch around). The investing membrane of the stomach, intestines, and other abdominal organs. PER-SPI-RA´TION (L. _perspi´ro_, to breathe through). The sweat, or watery exhalation of the skin; when visible, it is called _sensible_ perspiration, when invisible, it is called _insensible_ perspiration. PE´TROUS (Gr. [Greek: petra], _petra_, a rock). The name of the hard portion of the temporal bone, in which is situated the drum of the ear and labyrinth. PHAR´YNX (Gr. [Greek: pharunx], _pharunx_, the throat). The cavity between the back of the mouth and gullet. PHYS-I-OL´O-GY (Gr. [Greek: phusis], _phusis_, nature, and [Greek: logos], _logos_, a discourse). The science of the functions of living, organized beings. PI´A MA´TER (L.). Literally, the tender mother; the innermost of the three coverings of the brain. It is thin and delicate; hence the name. PLEU´RA (Gr. [Greek: pleura], a rib). A membrane covering the lung and lining the chest. There is one for each lung. PLEU´RI-SY. An inflammation affecting the pleura. PNEU-MO-GAS´TRIC (Gr. [Greek: pneumôn], _pneumon_, the lungs, and [Greek: gastêr], _gaster_, the stomach). The name of a nerve distributed to the lungs and stomach; it is the principal nerve of respiration. PNEU-MO´NIA (Gr.). An inflammation affecting the air-cells of the lungs. {261} PRES-BY-O´PI-A (Gr. [Greek: presbus], _presbus_, old, and [Greek: ôps], _ops_, the eye). A defect of the accommodation of the eye, caused by the hardening of the crystalline lens; the "far-sight" of adults and aged persons. PROC´ESS (L. _proce´do_, _proces´sus_, to proceed, to go forth). Any projection from a surface. Also, a method of performance; a procedure. PTY´A-LIN (Gr. [Greek: ptualon], _ptualon_, saliva). The peculiar organic ingredient of the saliva. PUL´MO-NA-RY (L. _pul´mo_, _pulmo´nis_, the lungs). Pertaining to the lungs.