P.
Palmated, webbed, as in the feet of some water-birds.
Papillæ, small dots or pimples.
Papillary, } having the surface covered with dots or pimples.
Papillous, }
Papillose, pimpled, dotted.
Papyraceous, thin as paper.
Parasitical, living on some other body.
Patulous, with a gap or opening.
Pearlaceous, of or like mother-of-pearl.
Partitions, calcareous processes, dividing the shells of the genus Nautilus, Serpula, &c.
Pectinated, resembling the teeth of a comb.
Pedicle, the support of the Lepas Anatifera, and its corresponding species, by which they are attached to wood, &c.
Peduncle, a foot-stalk or tube on which anything is seated.
Pediform, foot-shaped.
Pelagic, belonging to the deep sea.
Pellicle, the skin or film.
Pellucid, transparent, clear, bright.
Pentagonal, having five angles.
Perforated, pierced with holes.
Pervious, admitting passage.
Phosphorescent, emitting light in the dark.
Pillar, in univalves is the internal continuation of the columella or inner lips, and extends from the base to the apex.
Pinnated, winged.
Plaited, folded.
Plaits, folds.
Plicated, folded or plaited, as in the pillar of the volute tribe.
Plumose, having a feathery appearance.
Polythalmous, divided into several chambers.
Porcate, marked with raised longitudinal lines.
Porrected, projecting.
Prismatic, generally applied to the colours of shells, being like those of the prism; iridescent.
Produced, lengthened out.
Protrude, to thrust forward.
Protuberances, plaits higher or more elevated than the parts adjoining.
Punctuated, with small hollows like the punctures of a thimble.
Pyriform, pear-shaped.