236 LICHENACEI. [PARMELIA. 



British authors. From both, it may at once be distinguished by the per- 

 forate apothecia, and, when infertile, by the minutely reticulate rimulose 

 thallus. The apothecia are extremely rare in our islands, nor are the 

 spermogones present on our specimens. 



Hob. On mossy rocks and the trunks of old trees in maritime districts. 

 Distr. Rather local, though plentiful, in S. and W. England, N. Wales, 

 the W. Highlands of Scotland, the Channel Islands, and W. Ireland, 

 where it has once been gathered sparingly fertile. B. M. : Near Fort 

 Essex, Island of Alderney ; Island of Guernsey. St. Leonard's Forest, 

 Sussex ; Lyme Regis, Dorsetshire ; Carisbrook and near Ryde, Isle of 

 Wight; South Brent, Devonshire; Penzance and Withiel, Cornwall; 

 Dolgelly, Nannau, and Tan-y-Croes, Merionethshire ; Island of Anglesea. 

 Barcaldiue, Argyleshire. Dunkerron, co. Kerry (fruit) ; near Kyleniore, 

 Connemara, co. Galway. 



5. P. laevigata Ach. Syn. (1814) p. 212. Thallus suborbicular, 

 membranaceous, laciniato-lobed, glaucous-white or whitish ; be- 

 neath blackish and black-fibrilloso-rhizinose ; laciniso divaricately 

 sinuato-multitid or sinuato-incised, often subimbricate and whitish 

 tuberculato-sorediate at the apices, smooth or smoothish (K_ e w> 

 CaCl~, medulla K (CaCl) f+red). Apotbecia moderate or large, 

 badio-reddish, the margin entire or obsoletely crenulate or sore- 

 diate ; spores 6-8nsc, 0,012-13 mm. long, 0,007-8 mm. thick. 

 Gray, Nat. Arr. i. p. 442 ; Hook. Fl. Scot. ii. p. 55 ; Sm. Eng. Fl. v. 

 p. 200 ; Tayl. in Mack. Fl. Hib. ii. p. 148 ; Cromb. Lich. Brit. p. 33 ; 

 Leight. Lich. Fl. p. 139, ed. 3, p. 128. Parmelia sinuosa ft. Icevi- 

 f/ata, Mudd, Man. p. 92. Lichen Icevigatus, Sm. in Eng. Bot. xxvi. 

 (1808) t. 1852. Brit. Ems.-. Mudd, n. 69; Larb. Caesar, n. 64, 

 Lich. Hb. n. 124 ; Cromb. n. 141. 



The thallus is loosely attached to the substratum, often much ex- 

 panded and generally divided into narrow approximate lacinise. The 

 soredia occur at the apices, but are occasionally scattered over the surface 

 of the lacinise. From the allied species it is well separated by the thai- 

 line reactions. The apothecia are very rare, occurring chiefly in the 

 smaller corticole states, but the spermogones are not uncommon. They 

 are minute, dark-brown or blackish, irregularly scattered, with spermatia 

 about 0,005-7 mm. long, 0,001 mm. thick. 



Hob. On rocks, boulders, and trunks of trees, chiefly in maritime and 

 mountainous districts. Distr. Somewhat local, though usually plentiful 

 in S. and W. England, N. Wales, W. Highlands, Scotland, W. Ireland, 

 and in the Channel Islands. B. M. : Islands of Jeisey and Guernsey. 

 New Forest and Bournemouth, Hampshire ; Lustleigh Cleeve, Dartmoor, 

 Lynton, and Bolt Head, Devonshire; near Penzance and Withiel, Corn- 

 wall ; near Dolgelly, Aberdovey, and Barmouth, Merionethshire; Llan- 

 bei is and Beddgelert, Carnarvonshire ; Beaumaris, Island of Anglesea ; 

 Ashy, Cumberland. Inverary and Barcaldine. Argyleshire ; Ben Nevis, 

 Inverness-shire ; Glen Ach-na-Shilloch, Ross-shiie. Killarney, co. Kerry ; 

 Gougaumbara, co. Cork ; Connemara, co. Galway. 



6. P. xanthomyela Nyl. Flora, 1874, p. 306. Thallus externally 

 similar to that of P. lavirjata (K-f yellow), medulla sulphureous 

 (K + yellowish). Apothecia moderate or large, badio-reddish, the 



