. A monograph of lichens found in Britain; being a descriptive catalogue of the species in the herbarium of the British Museum. Lichens. 232 LICHUNACEI. [eTBENTA. Form 3. ceratea Nyl. Lich. Scand. (1861) p. 73.—Thallus de- cumbent ; laciniae narrow, convex and snbcylindrical, acuminate, Bubs;labrous.—Cromb. Grevillea, vi. p. 21.—Parmelia furfuracea ft. ceratea, Aeh. Meth. (1803) p. 255.—Brit. Exs.: Cromb. n. 139. Distinguished by the form of the more naked lacinise ; but intermediate states occm', in which these characters are less marked. With us it is always barren, though Acharius (Lich. Un
. A monograph of lichens found in Britain; being a descriptive catalogue of the species in the herbarium of the British Museum. Lichens. 232 LICHUNACEI. [eTBENTA. Form 3. ceratea Nyl. Lich. Scand. (1861) p. 73.—Thallus de- cumbent ; laciniae narrow, convex and snbcylindrical, acuminate, Bubs;labrous.—Cromb. Grevillea, vi. p. 21.—Parmelia furfuracea ft. ceratea, Aeh. Meth. (1803) p. 255.—Brit. Exs.: Cromb. n. 139. Distinguished by the form of the more naked lacinise ; but intermediate states occm', in which these characters are less marked. With us it is always barren, though Acharius (Lich. Univ. p. 501) says the apothecia chiefly occur in this form. Hah. On rocks and old walls in upland districts.—Distr. Seen only from a few localities in , Central, and N. England, S. and Scotland, and the , Highlands.—B. M.: Hunter Tor, Dartmoor, Devonshire ; Helminton, Cornwall; near Buxton, Derbyshire; Winder- mere, Westmoreland ; Alston, Cumberland. Pentland Hills, near Edin- burgh; Glen FaUooh, Perthshire; Deerhill Wood, Forfarshire; near Countesswells, Aberdeen. 42. PARMELIA Ach. Meth. (1803) p. 153 pro parte; Nyl. Syn. 1. (1860) p. 375.—Thallus foliaceous, horizontally expanded or rarely ascending, variously lobed and laciniate; epi- tballus somewhat shining, beneath usually fibrilloso- rhizinose; medullary layer woolly, composed of fila- ments loosely interwoven ; cortical layer thin, formed of minuto cells with thick- ened walls. Apothecia scat- tered, scutelliform, with thai- line margin; hypothecium colourless, thecae short, the wall thickened above ; spores usually 8n£e, ellipsoid, simple, colourless ; hjmenial gelatine bluish with iodine. Spermo- gones generally scattered, at length slightly prominent, blackish; sterigmata 2-5- articulate; spermatia acicular, fusiformi-inorassate at either apex. The species vary in habit, but are for the most part hori- zontally expanded, and rarely fruticulose. In no other genus are the reacdons of more val
Size: 893px × 2800px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectlichens, bookyear1894
