PHYSCIA.] PHYSCIEI. 301 



to be regarded as distinct, on account of its manner of growth, its being 

 much smaller in all its parts, and the absence of transition forms. It is 

 not very common in a fertile condition ; but the apothecia when present 

 are numerous. 



Hub. On rocks, walls, old pales, and the trunks of trees in maritime 

 arid upland districts. Distr. Rather local and not common in Great 

 Britain ; apparently rare in N. Ireland. B. M. : Hay Tor, Dartmoor, 

 Devonshire ; near "Penzance and St. Austell, Cornwall ; Windsor Park, 

 Berkshire; Wheattield Park, Oxfordshire; Colwall, Herefordshire; 

 Malvern, Worcestershire ; near Shrewsbury, Shropshire ; Aberdovey, 

 Merionethshire. Lawers, Killin, Perthshire; Findhaveu Hill, Forfar- 

 shire ; Durris, Kiucardineshire ; Lairg, Sutherlandshire. Co. Antrim. 



Form perfusa Nyl. ex Lamy Bull. Soc. Bot. t. xxv. (1878) p. 382. 

 Thallus smaller, widely expanded, densely stipate. Apotheciu 

 moderate. 



As stated by M. Lamy, I. c., this has the appearance of a granular 

 " minute, very crowded, thalline lacinia?. Our 



crust, though com 



British specimens are well fertile. 



Hab. On granitic walls of gardens and houses in maritime and upland 

 situations. Distr. Local, in N.E. Scotland and among the N. Grampians. 

 B. M. : Portlethen, Kincardineshire ; Crathie, Braemar, Aberdeen- 

 shire. 



Var. />. pygmsea Nyl. Lich. Scand. (1861) p. 108. Thallus 

 small, determinate ; laciniae erect, narrowly divided, often almost 

 rounded, the margin usually granuloso-pulverulent. Apothecia 

 moderate; spores 0,010-14 mm. long, 0,007-9 mm. thick. Bor- 

 rerapygmcea Bory in Fr. Lich. Eur. (1831) p. 73. 



Well distinguished from the type, with which, however, it is confluent 

 through intermediate stages, by the very much smaller (almost minute) 

 thallus, and by the nearly rounded lacinire. The thallus in our specimens 

 is in small, discrete nodules, and the apothecia, which are numerous, are 

 somewhat large in proportion to the size of the plant. 



Hab. On exposed granitic walls in an upland district. Distr. Extremely 

 local and scarce, among the S. Grampians, Scotland. B. M. : Ben Lawers, 

 Perthshire. 



B. CINERASCENTES. Thallus greyish or whitish, rarely brown. 

 Apothecia brownish or blackish ; spores 1-septate, brown or 

 dark-brown ; spermogones black, with spermatia cylindrical or 

 slightly thickened at either apex, rarely acicular. Eupliyscia 

 Cromb. Grevillea, xv. (1887) p. 78. 



a. Spermogones with cylindrical or subcylindrical spermatia. 



6. P. intricata Sena*. Enum. (1850) p. 11. Thallus expanded, 

 crcspitose, suberect, roundly compressed, laciniate, densely puberulo- 

 villosc, greyish-glaucous or greyish -brown ; beneath greyish-white, 

 subcanaliculate ; lacinias divaricately branched, very much en- 

 tangled (K~ , CaCl~). Apothecia lateral, sessile, moderate, plane or 



