LECIDEA] LECIDEACEJE 25 



Hob. On schistose rocks in mountainous regions. — Distr. Very 

 local in N. Wales, N. England, and the S. and N. Grampians, 

 Scotland. — B. M. Cader Idris, Merioneth ; Force Garth, Tessdale, 

 Durham ; Ben Lawers, Perthshire. 



26. L. arridens Nyl. in Flora lix. p. 573 (1876).— Thallus 

 somewhat scattered, very thin, plane, cracked, white or whitish 

 (K — , CaCl — ), often evanescent. Apothecia small, somewhat 

 plane, immarginate, irregular, bright rose-flesh-coloured, con- 

 colourous within, usually with an irregular spurious white 

 epithalline margin ; paraphyses slender, not crowded ; perithecium 

 with the epithecium and hypothecium colourless ; spores ellipsoid, 

 0,014-18 mm. long, 0,007-0,010 mm. thick ; hymenial gelatine 

 tawny-wine-red with iodine. — Cromb. in Grevillea v. p. 106 ; 

 Leight. Lich. Fl. ed. 3, p. 308. 



Has a slight resemblance to states of L. coarctata, but differs in the 

 absence of any thalline reactions, in the colour (persistent) of the 

 apothecia and of the epithecium, and in the shorter spores. In one of 

 the two specimens seen the thallus is determinate and small, with the 

 apothecia sparingly present ; and in the other it is diffuse and scarcely 

 visible, with the apothecia more frequent. 



Hab. On decomposed quartzose rocks in a mountainous district. — 

 B. M. Delphi, Connemara, Galway (the only locality). 



27. L. granulosa Sch^r. Spicil. p. 172 (1833).— Thallus effuse, 

 thinnish, granulose or leprose, whitish or glaucous- grey (K -f 

 yellowish, CaCl + reddish). Apothecia moderate, appressed, plane 

 or convex, variable in colour, brick-red, pale- or livid-brown, 

 blackish, white within, the margin thin, entire or flexuose, pale, 

 at length obliterated ; hypothecium colourless or pale-greenish- 

 yellow ; paraphyses coherent, thickisli and brownish at the 

 apices; spores oblong-ellipsoid, 0,009-16 mm. long, 0,004-7 mm. 

 thick ; hymenial gelatine slightly bluish then reddish or sordid- 

 violet with iodine. — L. decolorans Floerke inBerl. Mag. iii. p. 193 

 (1809); S. F. Gray Nat. Arr. i. p. 470 (1821); Hook. Fl. Scot. 

 ii. p. 39 ; Mudd Man. p. 197 ; Cromb. Lich. Brit. p. 66 ; Leight. 

 Lich. Fl. p. 261 ; ed. 3, p. 258. L. quadricolor Hook, in Sm. 

 Engl. Fl. v. p. 182 (1833) ; Tayl. in Mackay Fl. Hib. ii. p. 128. 

 Lichen granulosus Ehrh. Crypt. Exs. n. 145 (1785). L. quadricolor 

 Dicks. Crypt, fasc. iii. p. 15, t. ix. f . 3 (1793); Engl. Bot. t. 

 1185; With. Arr. ed. 3, iv. p. 24 (1796). Verrucaria dealorans 

 Hoffm. Deutschl. Fl. ii. p. 177 (1795). 



Exsicc. Leight. nos. 59, 352; Mudd n. 165; Larb. Lich. 

 Hb. n. 140. 



Well characterized by the versicolorous apothecia, the different 

 tints being apparently due to age ; these, however, are not always 

 present in the same specimen, some plants being merely unicolorous. 

 On bare moorlands it often spreads extensively, and when sterile and 

 associated with species of Cladina might be taken for their basal 

 crust. Wher lignicolous the thallus is thinner and usually more 

 pulverulent. The not unfrequent spermogones have the sterigmata 



