216 LICHKiVACEI. [CETRAKIA. 



gones are situated at the apices of the marginal cilia, with spermatia 

 6,005-6 mm. long, 0,001 mm. thick. A parasitic fungus, Spheeria cetra- 

 riicola Nyl., is occasionally seen on the thallus ; in Lapland it has been 

 seen also on C. hiascetis. 



Hab. On the ground among heath, and in stony places in upland, sub- 

 alpine, and especially in alpine situations. Distr. Not general nor com- 

 mon on the mts. of N. Wales, N. England, S.W. Ireland, and S. and N. 

 Scotland, but very plentiful amongst the Grampians, especially in Brae- 

 mar, where it occurs in fruit on some of the loftier summits: occasion- 

 ally descending to low altitudes on more exposed upland heath. B. M. : 

 Wootton Common, Norfolk; Stockton Forest, Langwith Moor, and Sten- 

 sball Common, Yorkshire ; Snowdon, Carnarvonshire ; Cwm Bychan, 

 Merionethshire; Teesdale, Durham. Cheviot Hills, Roxburghshire; 

 Pentland Hills, near Edinburgh ; Mael Graedha and Ben Lawers, Perth- 

 shire ; Clova Mts. and Sidlaw Hills, Forfarshire ; Hills of Nigg, near 

 Aberdeen ; Morrone, Lochnagar and Ben Macdhui, Braemar ; Ben Nevis, 

 Inverness-shire. Slieve Donard, co. Down ; Mangerton, co. Kerry. 



Form platyna Fr. Lich. Europ. (1881) p. 37. Lacinise rather 

 broad, subsimple and sparingly denticulate at the margins. Apo- 

 thecia large. Cromb. Grevillea, xv. p. 48 : Leight. Lich. Fl. p. 96, 

 ed. 3, p. 91 pro parte. Cetraria platyna Ach. Syn. (1814) p. 229. 

 Cetraria Islandica f. dilatala Norrl., Cromb. Linn. Soc. Journ. Bot. 

 1880, p. 575. Lichenoides rigid um eryngiifoliisreferens Dill. Muse. 

 209, t. 28. f. Ills. 



Varies in colour like the type, with the lacinize occasionally 1 inch in 

 breadth. The apothecia are usually rather large and few, with the mar- 

 gin generally excluded. From the paucity of the marginal cilia, the 

 spermogoues are rarely seen. 



Hab. On the ground among heaths in alpine places. Distr. Local on 

 the loftier Grampians, chiefly in Braemar, at high altitudes, where it is 

 not uncommon. B. M. : Lochnagar, Ben-naboord, Ben Macdhui, Cairn- 

 gorm, Cairntoul, Braemar, Aberdeenshire ; Ben Nevis, Inverness-shire. 



2. C. crispa Nyl. ex Lamy, Bull. Soc. Bot. Fr. xxv. (1878) p. 362. 

 Thallus somewhat small, caespitose, erect or depressed, pale-chest- 

 nut or chestnut-brown ; Jacinise crowded, rather narrow, canalicu- 

 late, densely ciliate and connivent at the margins, often reddish at 

 the base (K^, CaCl~). Apothecia small, submarginal, the margin 

 persistently denticulate ; spores as in the preceding species, or slightly 

 smaller. Cromb. Grevillea, xv. p. 48. Subsp. Cetraria. crispa, 

 Cromb. Grevillea, xii. p. 73. Cetraria Islandica ft. crispa Ach. Lich. 

 Univ. (1810) p. 513; Cromb. Lich. Brit. p. 26; Leight. Lich. Fl. 

 p. 97, ed. 3, p. 92. Cornicularia Islandica /3. crispa, Mudd, Man. 

 p. 77. lichen Islandicus fi Lightf. Fl. Scot. ii. p. 830 ; Huds. Fl. 

 Angl. ed. 2, p. 539 ; With. Arr. ed. 3, iv. p. 54. Lichenoides eryny'd 

 folia referens, tenuioribus et crispioribus foliis Dill. Muse. 212, t. 28. 

 f. 112. Brit, Exs. : Mudd, n. 52; Leight. n. 42 pro parte. 



Smaller, and somewhat pulvinate, with narrower and more ciliate lacinise 

 than C. Islandica, of which it was considered a variety, but is now sepa- 

 rated as a species by Nylander. The apothecia are very rare in Britain. 



