PERTUSARIA,] LKCANO-LECIDEET. 501 



The thallus spreads extensively and is occasionally of considerable 

 thickness. It is usually more or less covered with short, simple, con- 

 coloroiis papilhe which are at length fractured into rugose areolre. 

 When fei-tile the verrucfe are generally aggregate, becoming irregularly 

 lacerate. It is, however, more frequently sterile, and is then at times 

 the host of the parasitic Spiloma sphcerale Ach., which occurs also on the 

 form. 



Hah. On rocks, boulders, and walls in maritime and mountainous 

 regions. — Dhtr. Apparently general and common in Great Britain and 

 Ireland ; rare in tlie Channel Islands. — B. M. : Island of Sark. Dartmoor 

 Tors, Devonshire : St. Austell, Cornwall : Malvern Hills, AVorcestershire ; 

 Barmouth, Aberdovey, and Cwm Bycban, Merionethshire ; Island of 

 Anglesea ; Oswestry and Caer Caradoc, Shropshire ; Kildale Moor, 

 Cleveland, Yorkshire : Tee>dale, Durham. Ben Cruachan, Argyle.-hire ; 

 The Trossachs, Criaiilarich, Ben Lawers, and Craig Calliach, Perthshire; 

 Sidlaw Hills and Clova, Forfarshire : Glen Callater, Braeraar, Aberdeen- 

 shire. Dunken'on and Finnehy River, co. Kerry ; Dawros River, 

 Connemara, co. Gahvay. 



Form corallina Cromb. Grevillea, sii. (1SS3) p. 59. — Thallus 

 thick, densely papillose ; the papilke elongate, thin, simple and 

 branched. — P. ^[incarpa y. coralUnum Mudd, Man. p. 273. Isidiiim 

 coralUnum Gray, Nat. Arr. i. p. 412 : Turn. & Borr. Lich. Br. 

 p. 100; Hook. Fl. Scot. ii. p. 66 ; Sm. Eng. Fl. v. p. 231. Lichen 

 coralUnus Linn. Mant. (1767) p. 131 ; Huds. Fl. Angl. ed. 2, p. 526 ; 

 Lightf. Fl. Scot. ii. p. 808 ; With. Arr. ed. 3, iv. p. 16 pro parte ; 

 Eug. Bot. t. 1541. 



Differs from the type in the character of the isidioid papillse. It is, 

 however, connected with it by intermediate states, so that perhaps it is 

 to be regarded only as a luxuriant condition. It is never seen fertile. 



Hab. On rocks in maritime and upland situations. — Distr. Seen in 

 a tvpical state only from a few localities in Great Britain and Irelatid. 

 — B. M. : near Pont-ned-vechan, Brecknockshire ; Barmouth, Merio- 

 nethshire ; Island of Anglesea : A^-ton Moor, Cleveland, Yorkshire ; 

 Eo-lestone, Durham ; Alston, Cumberland. Ben-y-gloe, Perthshire ; 

 Baldovan Woods, Forfarshire. The Dargle River, co. Wicklow. 



15. P. ceuthocarpa Turn. & Borr. Lich. Br. (1839) p. 200 ; 

 Nvl. Mem. Soc. Cherb. t. v. p. 116. — Thallus determinate, thickish, 

 areolalo-diffract, cream-coloured ; the areolae convex, undulato- 

 rugose (K 4- yellow, then deep orange-red). — Apothecia few, in sub- 

 globose, smooth, conglomerate verructe ; the ostioles minute, 

 punctiform, blackish ; spores 2n3e, 0,150-1 7'"» mm. long, 0,057- 

 60 mm. thick. — Sm. Eng. Fl. v. p. 160 ; Mudd, Man. p. 271 ; 

 Cromb. Licb. Brit. p. 58 ; Leight. Angio. Lich. p. 2S, t. 9. f. 4 ; 

 Lich. Fl. p. 237, ed. 3, p. 22^. — Porina ceuthocarpa Tayl. in 

 Mack. Fl. Hib. ii. p. 102. Lichen ceuthocarpus Sm. Eng. Bot. xxxiii. 

 (1812) t. 2372.— Brit. Exs. : Leight. n. 284. 



Apparently an endemic species weU distinguished by the characters 

 given. The areoke are at times plane, especially towards the circum- 

 ference, where the plant is limited by a dai-k-olive hypothaUine margin. 



