484 LICHEN A CEI. [lECANORA. 



absent, so that the thallus is indeterminate and developed directly from 

 the prothallus (cfr. Nyl. Pyr. Or. p. 34). The apothecia when present, 

 for the plant is often sterile, at times remain persistently punctiform. 



Hob. On rocks, boulders, and walls from maritime to upland districts. 

 Distr. General and common in England ; rarer in Scotland and the 

 Channel Islands ; apparently very rare iu S. W. Ireland. B. M. : La 

 Moye and L'Etacq, Island of Jersey : Island of Alderney. Gorleston, 

 Suffolk ; near Hastings, Sussex ; Morwell Eocks, Devonshire ; near 

 Penzance, Cornwall ; Charnwood Forest, Leicestershire ; Ankerdine Hill, 

 Worcestershire ; Buckstone, near Monmouth, and Croesfaen, Monmouth- 

 shire; Barmouth, Dolgelly, and Aberdovey, Merionethshire; Llyn 

 Geirionydd, Carnarvonshire ; Oswestry and Haughmond Hill, Shropshire ; 

 Ayton and Guisboro' Moors, Cleveland, Yorkshire ; Eglestone, Durham ; 

 near Hexham, Northumberland ; Staveley, Kendal, Westmoreland. 

 King's Park, Stirling ; Ballachulish, Argyles'hire ; Craig Calliach, Perth- 

 shire ; Portlethen, Kincardineshire ; The Stocket, near Aberdeen ; Apple- 

 cross, Ross-shire. Dunkerron, co. Kerry. 



Var. p. peliscyphoides Nyl. Flora, 1872, p. 364. Thallus and 

 apothecia as in L. peliocypha, but the thalline reaction K (CaCl) + 

 reddish. Lecanora peliscypTia Cromb. Journ. Bot. 1873, p. 134; 

 Leight. Lich. FJ. ed. 3, p. 172 (quoad loc. cit.). 



A good variety entirely referable to this species, though externally 

 similar to the preceding, for which the British specimens were originally 

 taken. It is one of those lichens in which the Nylanderian reactions are 

 most useful for the discrimination of plants which otherwise might 

 readily be confounded. 



Hob. On walls in a maritime distinct. Distr. Only in N.E. Scotland, 

 where in the locality given I believe it is plentiful. B. M. : About 

 Portlethen, Kincardineshire. 



187. L. rufescens Nyl. Flora, 1872, p. 364, 1879, p. 356. 

 Thallus squamulose, rimoso-areolate or areolato-glebulose, reddish or 

 reddish-brown (K(CaCl)-), dark beneath. Apothecia immersed, 

 small, one or several immersed in each areola, at first concave then 

 somewhat plane, the thalline margin irregular; spores 0,003-4 mm. 

 long, 0,001 mm. thick ; hymenial gelatine bluish, then tawny with 

 iodine. Cromb. Grevillea, xix. p. 58. Urceolaria rufescens Sm. 

 Eng. Fl. v. p. 173. Leo'dect rufescens Borr. Eng. Bot. Suppl. 

 t. 2657. Acarospora cervina y. rufescens Mudd, Man. p. 159. 

 Endocarpon smaracjdalum $. rufescens Leight. Angio. Lich. p. 16, 

 t. 4. f. 4. Sagedia rufescens Turn, in Ach. Lich. Univ. (1810) 

 p. 329. 



Often confounded with L. ftiscata, but at once distinguished by the 

 negative thalline reaction. It is more nearly related to L. smarctffdula, 

 of which it may probably be the more developed and typical condition. 

 The apothecia are at times numerous and crowded. 



Hob. On rocks and walls, chiefly arenaceous, rarely schistose, in 

 maritime and upland districts. Distr. Only a very few localities in E. 

 and N. England, Wales, and the S.AV. Highlands of Scotland. B. M. : 

 Gorleston, Suffolk ; Dolgelly, Merionethshire : Ayton, Cleveland, York- 

 shire. Appin, Argyleshire. 



