480 LICHEN ACEI. [LKCANOKA. 



confounded, but, among other distinctive characters, differs essentially in 

 the type of the gonidia, which Jide Th. M. Fries (Lich. Scand. p. 289) 

 are 0,020-32 mm. in diameter. The British specimens are well fertile, 

 with the apothecia either scattered or several crowded (as in the figure 

 of Acharius) and then somewhat rlexuose at the margin. 



Hub. On calcareous and schistose rocks in upland and subalpine 

 districts. Distr. Very sparingly in N. England and among the 

 Grampians, Scotland. B. M. : Teesdale, Durham ; Mardale, Westmore- 

 land. Craig Calliach and Craig Tulloch, Perthshire ; Morrone, Braemar, 

 Aberdeenshire. 



180. L. chrysophana Nyl. ex Stiz. St. Gall. Nat. Ges. 1881, 

 p. 385. Thallus effuse, thin, rimuloso-areolate, sordid- or chesnut- 

 reddish, when dry at length dark green (K , CaCl ). Apothecia 

 minute, concave, blackish-green ; the thalline margin thin, at length 

 excluded; epithecium greenish; spores 8na>, ellipsoid, 0,009-12 

 min. long, 0,005-7 mm. thick ; hymenial gelatine bluish with 

 iodine. Cromb. Journ. Bot. 1882, p. 274. Asj)icilia chrysophana 

 Koerb. Syst. Lich. Germ. (1855) p. 159. 



Distinguished at once by the colour of the thallus and fruit from the 

 other British species of this subsection. The chrysogonidia (fide Arnold) 

 are 0,036-45 mm. long, 0,025-30 mm. thick. In our few specimens the 

 apothecia are rather scattered, though here and there a few are con- 

 gregate. 



Hab. On quartzose rocks and stones in alpine situations. Distr. 

 Extremely local and rare on two of the higher Grampians, Scotland. 

 B. M. : Above Loch-na-Gat, Ben Lawers, Perthshire ; Beu-nabuord, 

 Braemar, Aberdeenshire. 



0. Apothecia lecanorine, not immersed ; spores 8nae, simple, 

 colourless. Spermogones with subarticulate sterigmata and 

 ellipsoid spermatia. 



181. L. decincta Nyl. Flora, 1882, p. 452. Thallus determinate, 

 thin, smooth, rimulose, umbriue, greyish at the circumference 

 (K , CaCl ). Apothecia submoderate, plane, black, opaque, 

 internally subincolorous or brownish, the thallino margin not 

 prominent; spores 8nae, ellipsoid, 0.010-14 mm. long, 0,006-8 

 mm. thick ; paraphyses discrete, submoderate, thicker and brown 

 towards the apices ; hymenial gelatine pale-blue and then (especially 

 the thecse) tawny with iodine. Cromb. Grevillea, xii. p. 89. 



Allied to L. intercincta Nyl., with which it constitutes a distinct 

 section (vide Nyl. Flora, 1881, p. 531) characterized by the form of the 

 sterigmata and spermatia. From L. intercincta, which does not occur in 

 Britain, it differs chiefly in the colour of the thalline margin of the 

 apothecia and in the larger spores. In the single specimen seen the 

 apothecia are numerous, somewhat small, and the spermogones frequent, 

 with spermatia 0,0025-35 mm. long, 0,0015 mm. thick. 



Hab. On schistose rocks in a hilly locality. Distr. Very local and 

 scarce in N.W. England. B. M. : lied Screes, Westmoreland. 



