PLATYSMA. | CETRARIEI. 223 
(Ky yetlowieh’ CaC17).  Apothecia moderate, brownish-red, the 
receptacle externally plicato-rugose, the margin granulate; spores 
ellipsoid, 0,005-11 mm, long, 0004-6 mm. thick.—Cromh. Lich. Brit. 
p. 27; Leight. Lich. Fl. p. 101, ed. 3, p. 95.—Parmelia Fahlunensis 
Ach., Gray, Nat. Arr. i. p.441 ; Hook. Fl. Scot. ii. p. 53; Sm. Eng. Fl. 
v. p. 206; Mudd, Man. p. 100 pro parte. Lichen Fahlunensis Ach. 
Prodr. (1798) p.110; Huds. Fl. Angl. ed. 2, p. 532 pro parte; Eng. 
Bot. t. 653 (descript. non fig.); With. Arr. ed. 3, iv. p. 30 pro parte. 
Lichenoides tinctorium atrum, foliis minimis crispis Dill. Muse. 188, 
t. 24. f. 81.—The specimens in Herb. Linn. named Lichen Fahlu- 
nensis belong to the next species, as do specimens in the Herbaria of 
our older authors. To prevent the greatest confusion I have used 
the name applied by Acharius to this plant, and by which it has 
been usually designated. 
The thallus is parmelioid, occasionally somewhat expanded, with the 
laciniz more or less subascending. The apothecia are elevated, at first 
urceolate, at length becoming somewhat plane. The spermogones are 
frequent, brownish-black, in protuberant marginal papille, with spermatia, 
slender, elongate, 0,005 mm. long, 0,001 mm. thick. 
Hab. On rocks and boulders in subalpine and alpine places.—Distr. 
Local and scarce in §., W., and N. England, and N. Wales; more frequent 
among the Grampians, Scotland, especially in Braemar; not seen in 
Treland.—B. M.: Hay Tor, Dartmoor, Devonshire; Cader Idris, Merio- 
nethshire ; The Cheviots, Northumberland. Ben More and Ben Lawers, 
Perthshire; Clova Mts., Forfarshire; Lochnagar, Ben Macdhui, Aber- 
deenshire ; Ben Nevis, Inverness-shire. 
7. P. polyschizum Nyl. Flora, 1862, p. 82 (not.), 1869, p. 442.— 
Thallus orbicular, appressed, thickish, smooth, laciniato-divided, 
greyish- or dark-olive-brown, beneath paler or dark; lacinie short, 
narrow, imbricately crowded, subcanaliculate, slightly elevated at the 
margins, and rotundato-crenate at the apices (K_,CaCl_). Apo- 
thecia and spores as in the preceding species.—Cromb. Journ. Bot. 
1882, p. 272. 
This might be taken for a Hs ete condition of P. Fahlunense, with 
which it agrees in the form of the spermatia, but it is at once saparated 
by the absence of any reaction of the medulla. The thallus when mois- 
tened is of a greenish colour, and varies beneath from osseous-white to 
dark-spadiceous. In perfect specimens the lacinia are broader, planer, 
and less divided at the extreme circumference. When fertile the apo- 
thecia and spermogones are occasionally numerous and crowded. 
Hab. On rocks and boulders in alpine places.—Distr. Extremely local 
and scarce on one of the higher N. Grampians, Scotland.—B. M.: Ben- 
naboord, Braemar, Aberdeenshire. 
B. Spermatia ellipsoid. Thallus subascending, closely affixed, sub- 
concolorous; lacinie rather narrow. 
8. P. commixtum Nyl. Syn. i. (1860) p. 310, t. 8. f. 83.—Thallus 
suborbicular, adpresso-imbricate, smooth, laciniate, spadiceous or 
spadiceo-brownish, beneath nearly concolorous, with a few rhizinse 
