PARHELIA.] PARSIELTEI. 243 



A peculiar variety, which, notwithstanding the smooth thallus, is from 

 its general aspect referable to P. sulcvta rather than to P. saxatilis. At 

 the same time it is well distinguished by the esorediate thallus which is 

 but loosely affixed to the substratum, and by the form of the lacinise. 

 The under surface is occasional'y covered to the very extremities of the 

 lacinige with numerous densely crowded black rhizinie (form hirxuta 

 Cromb. I. c.). In the British specimens neither apothecia nor spermogones 

 are present. 



Hub. On the trunks of old fira and on granite walls in upland locali- 

 ties. Distr. Found only in two localities amongst the Grampians, Scot- 

 land. B. M. : Ben Lawers, Perthshire ; Durris, Kincardineshire. 



12. P. omphalodes Ach. Meth. (1803) p. 204. Thallus orbi- 

 cular, expanded, submembranaceous, somewhat shining, smoothish, 

 dark-brown, brownish-black or purplish-black ; beneath black, 

 densely rhizineo-fibrillose ; lacinise subtruncate at the apices 

 (KtrelKthen rusty red, CaClI). Apothecia dark-badious, mode- 

 rate or large ; otherwise as in P. saxatilis. Gray, Nat. Arr. i. 

 p. 440 : Hook. Fl. Scot. ii. p. 53 ; Sm. Eng. Fl. v. p. 199 ; Tayl. in 

 Mack. Fl. Hib. ii. p. 145. Purmelia saxatilis <$. omphalodes Mudd, 

 Man. p. 95; Cromb. Lich. Brit. p. 34; Leight. Lich. Fl. p. 138, 

 ed. 3, p. 127. Lichen omphalodes Linn. Sp. PI. (1753) p. 1143; 

 Huds. Fl. Angi. p. 446 ; Lightf. Fl. Scot. ii. p. 818; With. Arr. 

 ed. 3, iv. p. 34 ; Eng. Bot. t. 604. Lichenoides saxatile ti)ictorium, 

 foliis pilosis purpureis Dill. Muse. 185, t. 24. f. 80, in Hay, Syn. 

 ed. 3, p. 74, n. 70. Brit. Exs. : Leight. n. 7 ; Mudd, n. 67 ; Larb. 

 Caesar, n. 19 ; Bohl. n. 18. 



Though by some recent authors regarded as a variety of P. sa.vatilis, it 

 is entitled to rank as specifically distinct. It varies in colour from brown 

 or greyish-brown to nearly black, and is often, as observed by Hooker, 

 Eng. Fl. /. c., marked with pale zigzag cracks. In the darker thalli 

 the reaction of the cortical layer with K is less distinct. It often 

 spreads extensively, almost covering the larger and otherwise naked 

 boulders, and is somewhat variable. The apothecia are not unfrequent, 

 sometimes numerous and very large, becoming in old age angulose and 

 flexuose, often with slightly smaller spores as in P. sulcata. The spermo- 

 gones, which are also common, are usually more prominent than in 

 P. saxatilis, giving the thallus a black-punctate appearance. 



Hab. On rocks and boulders in maritime, upland, and alpine tracts. 

 Distr. General and common throughout Great Britain ; very abundant 

 in the Highlands, Scotland, to the summits of the higher mountains ; 

 apparently rare in Ireland and the Channel Islands. B. M. : Beauport 

 Bay, Jersey ; Island of Guernsey. Dartmoor, Hay Tor, and Lustleigh 

 Cleeve, Devonshire; Temple Moor, near Penzance, and Helminton, Corn- 

 wall ; Malvern Hills, Worcestershire ; near Oswestry, Shropshire ; Bar- 

 mouth and Cader Idris, Merionethshire ; Conway Mt., and Cwm Idwal, 

 Carnarvon ; Anglesea ; Cleveland, Yorkshire ; near Eglestone and Teesdale, 

 Durham : Kentmere, Westmoreland ; Cheviots, Northumberland. Moffat, 

 Dumfriesshire; Dalmahoy Crags, near Edinburgh ; Barcaldine and Appin, 

 Argyleshire ; Killin, Ben Lawers, Rannoch, near Dunkeld and Aber- 

 nethy, Perthshire ; Canlochan, Forfarshire ; near Invercauld, Craig 



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