74 COLLEMACEI. [LEPTocIUM. 
ed. 3, p. 31.—Collema tremelloides Hook. Fl. Scot. ii. p. 72; Sm. 
Eng. Fl. v. p. 213; Tayl. in Mack. Fl. Hib. ii. p. 111. Lichen 
tremelloides Linn. fil. Suppl. Pl. (1781) p. 450; Eng. Bot. t. 1981. 
Lichen cochleatus, Dicks. Crypt. fase. i. (1785) t. 2. f. 9; With. Arr. 
ed. 3, iv. p. 74.—Brit. Evs.: Cromb. n. 110; Larb. Lich. Hb. 
n. 3. 
Differs from LZ. Jacerwm in the larger smoothish thallus, leaden-coloured 
when dry, in the more rounded lobes with entire margins, and in the 
elevated, larger apothecia. The cortical layer is formed of rather large 
angular cells. Sparingly fertile in S.W. England and W. Ireland. 
Hab. Among mosses on moist rocks in maritime and mountainous 
districts— Distr, General, and usually plentiful in the Channel Islands, 
S. and W. Britain, and E. and 8.W. Ireland.—B. M.: St. Peter's Valley, 
Island of Jersey. St. Lawrence, Isle of Wight; near Brixkam, Saltash, 
Haberton, Conworthy, Wembury, and Totness, 8S. Devon; St. Issey and 
near Penzance, Cornwall; Tenby, Pembrokeshire ; Barmouth and Har- 
lech Castle, Merionethshire; Garn, Denbighshire; Llanberis Pass, Car- 
narvonshire; Island of Anglesea. Dumbarton Castle, Dumbartonshire ; 
Appin and Island of Mull, Argyleshire. Dunkerron Mt., Blackwater, 
and Killarney, co. Kerry ; Kylemore and Doughbraugh Mts., co. Galway. 
Form polyphyllum Nyl. ev Leight. Lich. Fl. ed. 3 (1879), p. 32. 
—Thalline lobes smaller, more divided and complicated, naked or 
isidiiferous. 
The thallus of this polyphyllous form when densely covered with isidia, 
as it usually is, is form pechneum (Ach. Syn. p. 343), Cromb. Grevillea, 
xv. p. 13. Not seen fertile. 
Hab. On damp rocks among mosses in maritime districts — Distr. Local 
and scarce in 8, England, the 8.W. Highlands of Scotland, and N.W. 
Treland.—B. M.: Near Torquay, 8. Devon. Island of Mull, Argyleshire. 
Near Kylemore, Connemara, co. Galway. : 
Subgen. 3. STEPHANOPHORUS Flot. Linnea, 1843, p. 16.— 
Thallus crowdedly plicatulate; apothecia with the thalline recep- 
tacle plicato-rugose. 
16. L, ruginosum Nyl. ea Cromb. Grevillea, xv. (1886) p. 13.— 
Thallus membranaceous, roundly lobed, plicate, longitudinally and 
crowdedly rugose, brownish- or greenish-lead-coloured, brownish- 
black-furfuraceous on the upper surface; lobes complicate, undulate, 
the margins entire or crenulate. Apothecia somewhat large, slightly 
concave or plane, red or brownish-red, the thalline margin thick, 
rugoso-plicate or furfuraceo-granulate ; spores ellipsoid or attenuate 
at both apices, 3-5-septate, and also sometimes longitudinally divided, 
0,020-37 mm. long, 0,010-17 mm. thick.—Collema ruginosum Duf. 
in Scher. Enum. (1850) p. 251. Leptogiwm chloromelum Mudd 
(non Nyl.), Man. p. 48; Carroll, Journ. Bot. 1867, p. 254; Cromb. 
Lich. Brit. p. 9; Leight. Lich. Fl. p. 32, ed. 3, p. 32. 
This can scarcely, even in an infertile state, be mistaken for any other 
British plant. It has sometimes been confounded with two exotic 
