378 APPENDIX III 



Pliocene (G. pleion, more, plus kainos, new), a Cenozoic geological period 

 above the Miocene; the Quarternary (Pleistocene) follows it. 



PNEUMA (G. air), a combining form, referring to breathing in anatomy; 

 Dipnoi, pneumogastric. 



PODA (G. pons, foot), a combining form; Apoda, Tetrapoda. 



POLY (G. polys, many), a prefix; polydactyl; polyembryony. 



PoLYPTERUS (G. polys, plus plerou, fin or wing), a genus of recent crossop- 

 terygian fish found in Africa. 



PONS (L. a bridge), specifically the pons Varolii, a large commissure of the 

 brain. 



PORTAL (L. porta, a gate), veins which break into capillaries before enter- 

 ing the heart; renal portal; hepatic portal, 



POST (L. after, behind), a prefix; posterior; post cardinal. 



PRE (L. before), prefix; precava; premolar. 



PREPUCE (L. praeputium, from pre, plus G. posthion, penis) the foreskin 

 of the penis covering the glans; specifically that of the primates. 



Primates (L. primus, first), an order of mammals including the lemurs, 

 monkeys, anthropoid apes and man. 



PRO (L. before, in front of), a prefix; procoelous, pronate. 



Proboscidea (G. pro, before, plus bosko, to feed), an order of mammals 

 with a proboscis or prolonged snout, including the African and Indian 

 elephants. 



proctodeum (G. proktos, anus, plus daio, to divide), the region of the 

 anus lined by invaginated ectoderm. 



pronephros (G. pro, plus nephros, kidnejO, the first embr3^onic kidney, 

 and the most anterior one; it disappears in the adults of all verte- 

 brates except the cyclostomes. 



PROSTATE (G. prostates, one in the front rank), a seminal gland of the 

 higher vertebrates (specifically the mammal) located near the exit 

 of the urethra from the bladder; the homologue of the Miillerian 

 ducts. 



Proterozoic (G. protos, first, plus zoon, animal), a Pre-cambrian Era, 

 later than the Archeozoic, covering an enormous length of time. 



Pterodactyla (G. pteron, wing, plus daktylos, finger), a group of extinct 

 flying reptiles with membranes stretched between the fingers. 



pteron (G. wing or fin), a combining form; pterygoid, Polypterus. 



PTERYGO-QUADRATE (G. pterou, plus L. quadratiis, square), the cartilage of 

 the upper jaw in vertebrates; its posterior end ossifies as the quad- 

 rate bone ; homologue of the incus. 



pubic (L. pubes, grown up), the lower hypogastric region, covered with 

 hair at maturity; pubic symphysis. 



pulmonary (L. pulmon, lung), relating to the lungs; pulmonary arteries 

 or veins. 



pylorus (G. pyloros, gate keeper), the ventral portion of the stomach; 

 pyloric sphincter, the constrictor muscle between the stomach and 

 duodenum. 



QUADRATE (L. Quadratus, square), the bone of the upper jaw articulating 

 with the articular of the lower jaw. See pterj^go-quadrate. 



RADIAL (L. radius, a ray), pertaining to a ray, radial cartilage; radius, a 

 bone of the forearm on the pre-axial side. 



