Phycolichens, lichens in which the gonidia are blue-green (Myxophyceae), [52] et passim.

Placodioid, thallus with a squamulose determinate outline, generally orbicular; [cf. effigurate], [80].

Placodiomorph, [see polarilocular].

Plectenchyma (Plectenchymatous), pseudoparenchyma of fungi and lichens, [66] et passim.

Pleurogenous, borne laterally on hyphal cells; [see spermatium], [312].

Pluri-septate, term applied to spores with several transverse septa, [321 et seq.]

Podetium, stalk-like secondary thallus of Cladoniaceae, [114], [293 et seq.]

Polarilocular, Polaribilocular, two-celled spores with thick median wall traversed by a connecting tube, [188], [340-341].

Polytomous, arising of several branches of the podetium from one level, [118].

Proper margin, the hyphal margin surrounding the apothecium, [157].