LECAXORA.] LECANO-LECIDEEI. 423 



thinly pruinose (epithecium CaCl ); thethalline margin undulate, 

 at length nearly obliterated ; spores ellipsoid, 0,011-13 mm. long, 

 0,006-7 mm. thick ; epithecium granulose, brown ; hymenial 

 gelatine bluish, the thecae violet with iodine. Leight. Lich. Fl. 

 p. 216, ed. 3, p. 205. Lecanora glaucoma var. subcarnea Mudd, 

 Man. p. 153 ; Cromb. Lich. Brit. p. 50. Lecidea subcarnea Sm. 

 Eng. Fl. v. p. 184. Lichen subcarneus Sw. Vet. Ak. Handl. 1791, 

 p. 126. Lichen pallescens With. Arr. ed. 3, iv. p. 2, pro parte. 



Usually regarded as a variety of the preceding species, but, among 

 other characters, at once differs in the reaction of the epithecium. The 

 thallus in entire specimens is subradiate at the circumference, but is 

 usually widely expanded. The apothecia are numerous, and occasionally 

 become substipitate. 



Hab. On rocks in maritime and upland mountainous districts. Distr. 

 Local in the Channel Islands, N. Wales, N. England, on the Grampians, 

 and in N.E. Scotland. B. M. : Boulay Bay, Island of Jersey; Island of 

 Alderney. Barmouth, Merionethshire ; Keighley and Ayton, Cleveland, 

 Yorkshire. Craig Tulloch, Blair Athole, Perthshire; near Porlethen, 

 Kincardineshire ; Morrone, Braemar, Aberdeenshire. 



102. L. fuscescens Nyl. Flora, 1872, p. 552, nota 1. Thallus 

 subdeterminate, thinly granulose, whitish or greyish (K + yellowish, 

 CaCl ); hypothallus thin, brownish-black. Apothecia small or 

 submoderate, adnate or adnato-sessile, plane, thinly margined, pale- 

 brown or blackish, internally whitish ; paraphyses submoderate, 

 blackish or brownish at the clavate apices ; spores globular or sub- 

 globose, 0,006-9 mm. long, 0,005-7 mm. thick ; hymenial gelatine 

 bluish, the thecae at length wine-coloured or tawny-reddish with 

 iodine. Cromb. Journ. Bot. 1875, p. 140 ; Leight. Lich. Fl. ed. 3, 

 p. 200. Lecidea fuscescens Somm. Suppl. Fl. Lapp. (1826) p. 161. 



Formerly regarded by authors as a Lecidea (Biatora), this, as pointed 

 out by Ny lander I. c., is in reality a Lecanora with gonidia intruded in 

 the margin of the apothecia. In a young state these are truly lecanorine, 

 though afterwards they become convex and immarginate so as to appear 

 biatoroid. In the British specimens, which are well fertile, the thallus 

 is rather scattered, with the hypothallus predominant. According to 

 Th. M. Fries (Lich. Scand. p. 461) the spermatia are " long, acicular, 

 curved." 



Hab. On trunks of birch in a mountainous district. Distr. Only 

 sparingly on one of the N. Grampians, Scotland. B. M. : Morrone, 

 Braemar, Aberdeenshire. 



c. Thallus uniform, K . 



103. L. umbrina Nyl. Bull. Soc. Bot. t. xiii. (1866) p. 369. 

 Thallus subefFuse, thinnish, granulato-unequal, sordid-greenish or 

 greyish (K , CaCl ). Apothecia somewhat small, plane, umbrine- 

 brown, at times slightly csesio-suffused ; the thalline margin thin, 

 whitish, subcrenulate ; spores 0,008-12 mm. long, 0,005-6 mm. 

 thick ; paraphyses thickish, jointed, brownish at the clavate apices ; 



