OF GREAT BRITAIN. 519 



Peridium, a membrane covering several hymenia. 



Perithelium,, the outer case, either entire or dimidiate, enclosing the hymenium 



as in Verrucarm. 

 Persistent, permanent or not falling off. 

 PUoso-ciliate, fringed or ciliated with hairs. 

 Pinnatifldo-dissected, cut in a pinnatifid mode. 

 Pinnat{fido-divaricate, divided into lateral segments which spread out in a 



divaricate manner. 

 Plane, flattened. 



Plano-appressed, flattened and closely pressed to a thing. 

 Piano-canaliculate, a plane surface channelled. 

 Piano-compressed, laterally pressed into a flat surface. 

 Piano-depressed, pressed downwards and flat on the upper surface. 

 Ptatyphyllous, broad-leaved. 

 Plicate, plaited. 



Plicato-deformed, deformed by being plaited. 

 Plicato-laciniate, lacinise arranged in a plaited manner. 

 Plicato-rugose, wrinkled in a plaited manner. 

 Plicato-undulate, plaited and wavy. 



Plicato-verrucoso-granulose, having plaited warty granules. 

 Plicatulate, minutely plaited. 

 Pliciform, plait-like. 



Plumbeo-alhicant, lead-colour becoming'whitish. 

 Plumbeo-ccerulescent, leaden-blue. 

 Plumbeo-cinerascent, leaden-ashy-grey. 

 Plumbeo-fuscescent, of a brownish-lead-colour. 

 Plw/mbeo-glaucescent, of a glaucous-lead-colour. 

 Pkumbeo-virescent, of a lead-coloured-green. 

 Plurirovrticulate, with many articulations or joints. 

 Plurilocular, many-celled. 

 Pluriseptate, having many septa. 

 Podetiiform, resembling a podetium. 

 Podetiiformi-stipitate, having a stipes like a podetium. 

 Podetium, the stem-like portion of the thallus in the genus Cladonia, which 



bears on its apex the apothecium. 

 Pedicellate, stalked. 



Polari-bilocular, a spore with the cells placed at the opposite apices. 

 Polari-nucleolate, having nuclei in the opposite apices of a spore. 

 Polygonal, of many angles. 

 Polymorphous, of many forms. 

 Polyphyllous, many-leaved. 

 Polysporous, having asci containing numerous spores or more than the usual 



number of 8. 

 Poriform, like a pore. 



Predominant, very conspicuous and in excess. 

 Proliferous, bearing marginal buds or lobes. 



ProUferously-denticuJate, the marginal teeth becoming proliferous. 

 Prominent, projecting or elevated. 

 Proper margin, the margin of the apothecium formed from the apothecium 



itself and not from the thallus. 

 Prostrate, lying flat on a surface. 

 Protoplasm, elementary matter. 

 Protruded, thrust out or forwards. 



Pseudo-Uatorine, falsely bialorine, or having an apothecium without a conspi- 

 cuous thalline margin, but at the same time without any observable proper 



margin or convex and immarginate. 

 Pseudo-cyphellas, minute excavations on the under surface of the thallus filled 



with white or yellow powder. 

 Pseudo-cyphellate, having false or imperfect cyphellse. 

 Pseudo-disciform, falsely disk-like. _ 

 Pseudo-scutelliform, falsely shield-like. 

 Pseudo-thallodal, apparently formed of the thallus. 

 Puberulo-villose, with pubescent hairs. 

 Pulpy, formed of pulp, springy and elastic. 

 Pulveraceous, powdery. 

 Pulvereous, powdery. 

 Pulmreo-granulose, with powdery granules, 



