GLOSSARY xxi 



Intricate cortex, composed of hyphae densely interwoven but not coalescent, 83. 

 Isidium, coral-like outgrowth on the lichen thallus, 149-151. 



Lecanorjne, apothecium with a thalline margin as in Lecanora, 158. 



Lecideine, apothecium usually dark-coloured or carbonaceous and without a thalline 



margin, 158. 

 Leprose, mealy or scurfy, like the old form genera. Lepra, Lepraria, 191. 

 Lichen-acids, organic acids peculiar to lichens, 221 et seq. 

 Lignicolous, living on wood or trees, 366. 

 Lirella, long narrow apothecium of Graphideae, 158. 



Mazaedium, fructification of Coniocarpineae,'the spores lying as a powdery mass in the 



capitulum, 176. 

 Medulla, the loose hyphal layer in the interior of the thallus, 88 et passim. 

 Meristematic, term applied by Wainio to growing hyphae, 48. 



Microgonidia, term applied by Minks to minute greenish bodies in lichen hyphae, 26. 

 Multi-septate, term applied to spores with numerous transverse septa, 316 et seq. 

 Murali-divided, Muriform, term applied to spores divided hke the masonry of a wall, 187. 



Oidium, reproductive cell formed by the breaking up of the hyphae, 189. 



Oil-cell, hyphal cell containing fat globules, 215. 



Orculiform, see polarilocular. 



Orthidium, supposed new type of fructification in lichens, 192. 



Palisade-cells, the terminal cells of the hyphae forming the fastigiate cortex, 82, 83. 



Panniform, having a felted or matted appearance, 260. 



Paraphysis, sterile filament in the hymenium, 157. 



Parasymbiosis, associated harmless but not mutually useful growth of two organisms, 263. 



Parathecium, hyphal layer round the apothecium, 157. 



Peltate, term applied to orbicular and horizontal apothecia in the form of a shield, 336. 



Perithecium, roundish fructification usually with an apical opening (ostiole) containing 



ascospores, \^% et passim. 

 Pervious, referring to scyphi with an opening at the base {Perviae), n8. 

 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. 



Plectenchjrma (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, 1 88, 340-341. 

 Polytomous, arising of several branches of the podetium from one level, n8. 

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

 Prothallus, Protothallus, first stages of hyphal growth ; cf hypothallus, 71. 

 Pycnidiospores, stylospores borne in pycnidia, 198 et passim. 

 Pycnidium, roundish fructification, usually with an opening at the apex, containing 



sporophores and stylospores ; cf. spermogonium, 192 et seq. 

 Pyrenolichens, in which the fructification is a closed perithecium, 173 et passim. 



Radiate thallus, the tissues radiate from a centre, 98 et seq. 



