{a 
32 CYCLOCARPINEE [PLACYNTHIUM 
p. 126 (1861); subsp. psotina Cromb. in Journ. Bot. xi. p. 133 
(1873). Pannaria psotina Leight. Lich. Fl. ed. 3, p. 156 (1879). 
Pannularia nigra subsp. psotina Cromb, in Grevillea xviii. p. 44 
(1889) & Monogr. i. p. 343. 
Ezxsice. Johns. nos. 30, 255. 
Outwardly like the species, but with a lighter coloured hypothecium 
and with more pronouncedly 3-septate spores, which are sometimes 
irregular and blunt at the ends. 
Hab. On caleareous rocks and mortar of walls in maritime and 
inland districts.—Dzistr. Rare in the Channel Islands, England and 
W. Ireland.—ZB. M. The Vale, Guernsey; Eastbourne, Sussex; near 
the Horse, Windsor Great Park, Berks; Whitehaven, Cumberland; 
Hexham, Northumberland; Westport and Castlebar, Mayo. 
Form triseptatum Hue in tom. cit. p. 148.—Thallus sub- 
determinate, granular-crustaceous, cracked-areolate, brownish- 
black ; hypothallus blackish, not very distinct. Apothecia 
rather small, with a thin proper margin, brownish-black, inter- 
nally whitish; spores ellipsoid, 3-septate, 16-22 long, 6-9 
thick.—Pannaria nigra f. triseptata Nyl. Lich. Scand. p. 126 
(1861); Cromb. Lich. Brit. p. 43; subsp. triseptata Nyl. ex 
Cromb. in Grevillea i. p. 171 (1873). Pannularia triseptata Ny. 
ex Cromb. in op. cit. xviii. p. 44 (1889); Cromb. Monogr. i. 
p. 343. 
With slightly larger spores and more crustose thallus than in the 
species. 
Hab. On mica-schist rocks in mountainous regions.— Distr. Rare 
among the Scottish Grampians.—%. M. Achrosagan Hill, Appin, 
Argyll; Craig Calliach and Ben Lawers, Perthshire. 
2. P. delicatula A. L. Sm.—Thallus thin adnate, minutely 
granular-crustaceous, brown. Apothecia small, somewhat convex, 
brownish-black (reddish when moist); hypothecium colourless ; 
paraphyses yellowish-brown at the clavate apices ; spores fusiform- 
vermicular, straight or substraight, 7—9-septate, 40-76 » long, 
5-7 » thick; hymenial gelatine and asci bluish with iodine.— 
Arctomia delicatula Th. Fr. Lich. Arct. p. 287 (1860). Pannularia 
delicatula Nyl. ex Cromb. in Journ. Bot. xx. p. 274 (1882) ; 
Cromb. Monogr. i. p. 345. 
Placed in the genus Placynthiwm on account of the plectenchy- 
matous homoiomerous thallus, and the multi-septate spores. 
Hab. On decayed mosses in alpine situations.—Distr. Extremely 
rare among the S. Grampians, Scotland, and Mts. of W. Ireland 
(Connemara, Galway).—B. M. Ben Lawers, Perthshire. 
13. SCHIZOMA Nyl. ex Cromb. in Grevillea v. p. 108 (1877) 
(note). (Pl. 13.) 
Thallus laciniate-linear, gelatinous when moist, non-corticate. 
Algal cells Scytonema. Apothecia unknown. Spermogones 
