272 LICHENACEL. [LOBARIA. 
reum maximum Dill. in Ray Syn. ed. 3, p. 76, n. 86.—Brit. Eas. : 
Leight. n. 74; Mudd, n. 64; Cromb. n. 37. 
The familiar “Tree Lungwort,” when fully developed, is one of the 
largest, as it is one of the most common, of the British species of this 
tribe. It varies considerably in the breadth and divisions of the lobes, 
old plants being much broader and less laciniate, The thallus, which 
hangs loosely from the trunks on which it grows, is more or less shining, 
especially in young plants, while the lacinizw are often whitish sorediate 
and isidiate at the margins. Usually also seriately arranged soredia and 
occasionally isidia are present in the coste between the faveole. States 
in which the isidia are numerous and crowded form the variety papillaris 
Del, Stict. p. 144, t. 17. f. 63. With us it is comparatively rare in a 
fertile condition, though the apothecia are sometimes very numerous. 
Hab. On the trunks of forest trees, especially old oaks, in mountainous 
regions, rarely on mossy rocks in maritime districts.— Distr. General and 
for the most part plentiful in the Channel Islands, the more Western 
tracts of Great Britain, and probably of Ireland ; fruiting more freely in 
the 8.W. Highlands of Scotland.—B. M.: Boulay Bay, Island of Jersey; 
Island of Guernsey. Near Loughton, Essex; near Lydd, Kent; Ryde 
and Appuldurcomb, Isle of Wight; New Forest, Hants; Lydford, Tot- 
nes, Buckfastleigh, and Ivy Bridge, Devonshire ; Boconnoc, Pentire, St. 
Minver, and near Penzance, Cornwall; Bryer Island, Scilly ; Chedworth 
Woods, near Cirencester, Gloucestershire; Bagley Wood, near Oxford ; 
Charnwood Forest, Leicestershire; near Ludlow, Shropshire. Cader 
Idris, Rhewgreidden, Aberdovey, and Barmouth, Merionethshire ; near 
Dolgelly, Bettws-y-Coed, Denbighshire; Conway and Devil’s Bridge, 
Carnarvonshire ; Beaumaris, Island of Anglesea; Kildale, Cleveland, 
Yorkshire; Eglestone and Teesdale, Durham; near Grassmere, West- 
moreland; Cheviots, Northumberland; Patterdale and Calder Abbey, 
Cumberland. New Galloway, Kirkcudbrightshire; near Moffat, Dum- 
friesshire ; Pentland Hills and Turtin Hill, near Edinburgh ; Inverary, head 
of Loch Awe, Barcaldine, and Appin, Argyleshire; The Trossachs, Loch 
Katrine, and Killin, Perthshire; Reeky Linn, Lundie Craigs, and Clova, 
Forfarshire ; Dunottar Castle, Kincardineshire; Craig Cluny and Cor- 
riemulzie, Braemar, Aberdeenshire ; 8. of Fort William, Inverness-shire ; 
Applecross, Ross-shire. Dinish and Ronayne’s Island, Killarney, co. 
Kerry ; Lough Inagh, co. Galway. 
Var. pleurocarpa Ach. Lich. Univ. p. 450 (Cromb. Exs. n. 137), isa 
state in which the apothecia are abortive, tuberculoso-difform and brown- 
ish-black in consequence of being the host of Cehkdium stictarum, Tul. 
In the Museum herbarium there are specimens showing this condition 
from the following localities:—Bocconoe, Cornwall; Hafod, Cardigan- 
shire; Cwn Bychan, Merioneth. Appin and head of Loch Awe, Argyle- 
shire; The Trossachs, Perthshire ; Cawdor Woods, Nairn. 
Form 1. hypomela Cromb. Grevillea, xv. (1887) p. 76.—Thallus 
with the interstices of the under surface reticulate with black rhi- 
zine. Apothecia with the thalline margin rugoso-crenulate.—Sticta 
pulmonacea var. hypomela Del. Stict. (1825) p. 144, t. 17. f. 64; 
Nyl. Syn. i, p. 852.—Brit. Evs.: Cromb. n. 136. 
Approaches L. retigera (Ach.), an exotic species, in the character of the 
thallus beneath, which probably results from the habitat, the type itself 
at times having the rhizine dark brown. With us it is seldom well 
fruited. 
