476 LICHENACEI. [LECANOKA. 



and on the S. and Central Grampians, Scotland. B. M. : Guns-wick Scar, 

 Westmoreland. Craig Calliach, above Loch-na-Gat, Ben Lawers, and 

 Craig Tulloch, Blair Athole, Perthshire. 



1 74. L. poriniformis Nyl. Flora, 1865, p. 353 Tliallus effuse, 

 thinnish, firm, rimoso-difFract, greyish or pale-grey (K + yellow). 

 Apothecia smsill, innate in convex, somewhat prominent verrucae, 

 pertusarioid, pale or brownish ; the epithecium pale, punctiformi- 

 contracted ; spores 6-8na3, ellipsoid, 0,070-80 mm. long, 0,034-50 

 mm. thick; paraphyses slender; hymenial gelatine bluish, then 

 tawny-yellow with iodine. Carroll, Jouru. Bofc. 1866, p. 23 ; 

 Cromb. Lich. Brit. p. 56; Leight. Lich. Fl. p. 190, ed. 3, p. 203. 

 Brit. Exs. : Cromb. n. 74. 



Looks exactly like a Pertusaria, allied to P. xanthostoma Somm. 

 The characters, however, of the hymenium, of the thecae (which are 

 fugacious), and of the spores show that it is a Lecanora distantly related 

 to the preceding species. The thallus spreads somewhat extensively 

 with the fertile verrucae scattered or approximate. Usually there is but 

 a single apothecium in each verruca, though not unfrequently there are 3 

 or 4, when the verrucas are rather larger. 



Hab. On schistose rocks and walls, rarely incr listing mosses, or on 

 trunks of old firs, in maritime and subalpine districts. Distr. Local and 

 scarce among the S. and Central Grampians and on the N.E. coast of 

 Scotland. B. M.: Ben Lawers and Craig Tulloch, Perthshire; near 

 Portlethen, Kincardineshire. 



175. L. Dicksonii Nyl. ex Carroll, Journ. Bot. (1867) p. 255. 

 Thallus determinate, thin, smooth, rimose or areolato-rimose, 

 ochraceo-ferruginous, opaque (K , CaCl ); hypothallus thin, 

 black, limiting the thallus. Apothecia lecideine, small, innate, 

 concave, black, internally blackish (greyish in the centre), the 

 proper margin thick, black ; spores 8nae, ellipsoid, 0,011-14 mm. 

 long, 0,006-8 mm. thick ; hypothecium brownish-black ; paraphyses 

 not discrete, fuliginous towards the apices ; hymenial gelatine 

 bluish, then wine-red with iodine. Cromb. Lich. Brit. p. 55 ; 

 Leight. Lich. Fl. p. 211, ed. 3, p. 196. Lichen Dicksonii Ach. 

 Prodr. (1798) p. 76. Lecidea melanophcea Fr., Mudd, Man. p. 206. 

 Lecidea (Ederi (non Web.) Tayl. in Mack. Fl. Hib. ii. p. 122 ; Sm. 

 Eng. Fl. v. p. 178 ; Hook. Fl. Scot. ii. p. 38 ; Gray, Nat. Arr. 

 i. p. 466. Lichen (Ederi Eng. Bot. t. 1117 ; With. Arr. ed. 3, iv. 

 p. 11 pro parte. Brit. Exs.: Leight. n. 127 ; Cromb. n. 72. 



By many authors regarded as a Lecidea, with much the aspect of 

 L. (Ederi, with which it has been confounded ; but its most appropriate 

 place is in this section. The peculiar colour of the thallus, as in various 

 other instances, is owing to suffusion with peroxide of iron. Typically, 

 according to specimens from Kerguelen Land, it is greyish (vide Linn. 

 Soc. Journ. Bot. xv. p. 190 s. n. Lecidea sincenda Nyl.). The apothecia 

 are numerous and at times somewhat crowded. 



.Hab. On rocks and walls, chiefly schistose, in mountainous regions. 

 Distr. Somewhat local, though usually plentiful in Great Britain and in 



