PARMELIA | PARMELIACEA 131 
Bot. vi. p. 163 (1847); Cromb. in Journ. Bot. xx. p. 272 (1882). 
Lichen tiliaceus Sm. Engl. Bot. t. 700 (1800). 
Distinguished from the species by the dark setulose under surface 
of the base of the apothecium. The dark fibrils are not always 
easily seen. In Engl. Bot. t. 700 they are omitted, though quite 
clearly indicated in one of Sowerby’s unpublished drawings, and 
present in the specimen of Lichen tiliaceus preserved in the British 
Museum. 
Hab. On the trunks of trees in wooded districts.—Distr. Not 
uncommon in the Channel Islands and 8. England.—B. M. Jerbourg, 
Guernsey; Chagford, Ashburton, Cornworthy, and near Torquay, 
Devon; Dunster Tower, Somerset; Lymington, Hants; near Ryde, 
I. of Wight. 
Isidia or Soredia on surface of lobes. 
16. P. scortea Ach. Lich. Univ. p. 461 (1810).—Thallus 
orbicular, spreading, coriaceous, whitish, more or less densely 
covered towards the centre with darker isidia, the lobes short, 
rounded-crenate ; beneath densely black rhizinose to the margin 
(K + yellowish’ CaCl + reaaisn)- Apothecia moderate in _ size, 
scattered, reddish-brown, the margin subentire; spores 7-11 p 
long, 5-7 p thick.—Hook. in Sm. Engl. Fl. p. 199. P. tiliacea 
var. scortea Mérat Nouv. Flor. envir. Paris ed. 4, i. p. 393 
(1836); Mudd Man. p. 93; Leight. Lich. Fl. p. 131; ed. 3, 
p- 122. Subsp. scortea Cromb. Lich. Brit. p. 33 (1870). Lichen 
scorteus Ach. Lich. Suec. Prodr. p. 119 (1798); Engl. Bot. 
t. 2065. 
Evwsicc. Larb. Cesar. n. 18; Leight. n. 87. 
Differs from P. tiliacea in the slightly thicker isidiose thallus. <A 
specimen from Bolt Head, Devon, with small congested lobes, has 
been described as f. concrescens Cromb. Monogr. i. p. 240 (1894). 
Hab. On trees and old palings, rarely on rocks in maritime and 
inland districts.—Dist7. Rare in the Channel Islands, England and 
Wales, S. and W. Scotland and 8.W. Ireland.—B. M. L’Etacq, Jersey ; 
Sark; Bolt Head, Devon; Shanklin, I. of Wight; New Forest, Hants ; 
Stonehenge, Wilts; near Lewes and Henfield, Sussex; Harboro’ 
Magna and Newbold-on-Avon, Warwickshire; Twycross, Leicester- 
shire; Little Stretton, Shropshire; Holyland, Pembrokeshire ; 
Llanforda and near Barmouth, Merioneth; Stokesley, Cleveland, 
Yorkshire; near Egglestone, Durham; near Kendal, Westmoreland ; 
Castle Douglas, Kirkcudbrightshire; West Kilbride, Ayrshire; Askew 
Wood, Dunkerron, Kerry. 
17. P. proboscidea Tayl. in Mackay FI. Hib. ii. p. 143 (1836) 
(non Allioni ex Ach. Lich. Univ. p. 458 (1810)).—Thallus 
moderate in size or wide-spreading often bearing isidia changing 
into soredia over the surface, glaucous- or whitish-grey, the lobes 
imbricate, crisp and crenate or often finely dissected at the 
margins, cilia present on the margins and generally associated 
with the isidia on the surface ; beneath black, densely rhizinose, 
generally naked and brown at the edge (K + yellow, then red). 
ae 
