490 XICHEXACEI. [LECANOBA. 



197. L. simplex Nyl. in Cromb. Lich. Brit. (1870) p. 57. 

 Thallus obsolete. Apothecia lecideine, minute, plane, or concave, 

 variously corrugate or plicate, black, the margin flexuose and irre- 

 gularly crenate ; spores very numerous, 0,003-6 mm. long, about 

 0,001-2 mm. thick ; hymenial gelatine bluish, then wine-red with 

 iodine. Lecanora squamulosa form simplex Leight. Lich. Fl. p. 185, 

 ed. 3, p. 170. Acarospora cervina t. simplex Mudd, Man. p. 160. 

 Lecidea simplex Sm. Eng. Fl. v. p. 179 ; Tayl. in Mack. Fl. Hib. ii. 

 p. 124. Lichen simplex Dav. Trans. Linn. Soc. ii. (1794) p. 283, 

 t. 28. f. 2 j With. Arr. ed. 3, iv. p. 5 ; Eng. Bot. t. 2152 (two left- 

 hand figs.). Rinodina privigna, Gray, Nat. Arr. i. p. 450. Brit. 

 Exs. : Leight. nos. 272, 273. 



Well characterized by the form of the fruit and the very minute spores. 

 Occasionally there are traces of a very thin, dark-brown or blackish 

 thallus, but this is evidently foreign. The apothecia are rather variable, 

 often crowded, rotundate or somewhat angular, with the disc, which is 

 constantly black even when moistened, but little visible. When more 

 rotundate with the disc rugose and the margin involute and rimulose, it 

 is form strepsodina (Ach.) (Opegrapha Persoonii y. strepsodina Lich. 

 Univ. p. 247). When more angulose and much gyroso-plicate as if gyro- 

 phoroid it is form complicate, Cromb. Grevillea, xtx. p. 58. Both of 

 these, however, pass into and are frequently mixed up with more typical 

 conditions. 



Hub. On rocks, chiefly schistose and calcareous, in maritime and moun- 

 tainous districts. Distr. Here and there throughout Great Britain and 

 the Channel Islands ; apparently rare in W. Ireland. B. M. : La Move, 

 Island of Jersey ; Chateau Point, Island of Sark. Buckfastleigh, A?h- 

 burton and Ilfracombe, Devonshire ; Tintagel, Withiel, and Penzance, 

 Cornwall ; Barmouth, Dolgelly, and Capel Arthog, Merionethshire ; 

 Bangor, Carnarvonshire ; Island of Anglesea ; north of Douglas, Isle of 

 Man ; Hexham, Northumberland. Baroaldine and Ballachulish, Argyle- 

 shire ; Craig Calliach, Ben Lawers, and Craig Tulloch, Perthshire ; South 

 of Bay of Nigg, Kincardineshire ; Craig Guie and Morrone, Braemar, 

 Aberdeenshire. Dunkerron, co. Kerry ; Glencorbol, Connemara, co. 

 Galway. 



Form herpes Cromb. Grevillea, xix. (1891) p. 58. Apothecia very 

 minute, punctiform, impressed. Sarcoyyne simplex var. herpes 

 Norm. Bot. Not. 1873, p. 34. 



Readily overlooked from being, scarcely visible to the naked eye. 

 Probably it is only a poorly developed state depending on the nature of 

 the substratum. 



Hob. On shady schistose rocks in a maritime locality. Distr. Only 

 very sparingly in the W. Highlands of Scotland. B. M. : Ballachulish, 

 Argyleshire. 



61. DIRINA Fr. PI. Horn. (1825) p. 244; Nyl. Mem. Soc. 

 Cherb. iii. p. 180. Thallus crustaceous, continuous or rimulose, 

 containing chrysogonidia. Apothecia tuberculoso-lecanorine ; spores 

 8ne, fusiform, 3-septate, colourless ; hypothecium thick, black ; 

 paraphyses slender, not very discrete ; hymenial gelatine wine- 



