Plan´tar, a. Pertaining to the sole. A certain muscle is the plantaris.
Plan´tigrade, a. Walking on the back of the tarsus as well as on the soles of the toes. Many pygopodous birds are plantigrade.
Plas´ma, n. Colorless fluid of the blood.
Plas´tic, a. That may be moulded. Forming or serving to form; histogenetic. Plastic force. See Nisus Formativus.
Pleu´ra, n. Membrane lining the thorax and investing the lungs.
Pleurapoph´ysis, n. Segment of the hæmal arch next to the centrum. The vertebral rib of a bird is a pleurapophysis.
Plex´us, n. Union in network of nerves, vessels, or fibres. Said especially of the anastomosis of nerves.
Pli´ca Ala´ris, or Pli´ca Preala´ris, n. The feathered fold of skin on the front border of the wing stretched by an elastic tendon from the shoulder to the wrist, rendering the smooth straight anterior border of the wing. (Plica alaris is rarely used for the fold or bend of the wing.)
Pli´ca Interdigita´lis, n. Webbing between the toes. Same as palama.
Pli´cæ Primiti´væ, n. pl. Primitive folds; certain parallel lines observed in the early embryonal trace.