BRITISH LICHENS

LECIDEA LECIDEACElE 101
more or less scattered, pale- or olive-greyish (K -, CaCI -) ;
hypo thallus very thin, black. Apothecia minute, innate, plane,
margined, black, the margin slightly prominent; hypothecium
brown; paraphyses concrete; epithecium bluish-brown; spores
minute, oblong-ellipsoid, 6--8 [L long, 3-4 (.L thick; hymenial
gelatine pale-bluish then tawny with iodine.-Cromb. in Journ.
Bot. xx. 275 (1882). L. perustu1a Ny!. 1. c. 221; Cromb. in
GreviIIea viii. 29. L. nitida Leight. Lich. Fl. ed. 3, 295, pro parte
(non Schoor.).
Exsicc. Leight. n. 278 (as L. juscoatra var.).
Resembles a diminutive state of L. jU8coatra, but differs in the
absence of any thalline reactions and the much smaller spores. The
numerous inconspicuous apotheeia occasionally have the margins paler.
The predominant black hypo thallus gives a very dark appearance.
Ilab. On siliceous rocks in maritime and mountainous districts.­
Dilltr. Only a few localities in Wales and W. Ireland, probably overlooked
elsewhere.-B. M. Barmouth, Merioneth; lJanberis, Carnarvonshire;
Dunkerron, Kerry; Doughruagh Mt., Connemara, Galway.
179. L. endomelaena Leight. in Trans. Linn. Soc. (Bot.) ser.
2, i. 239, t. 32, figs. 13 & 14 (1878).-Thallus pale-greyish-green,
opaque, granular, the granules large, scattered or aggregate,
convex, composed of minute conglomerate convex roundish Ot·
sublobate subfurfuraceous squamules (K + pale-yellow, CaCI +
pale-yellow). Apothecia violet-black, rather large, innate-sessile,
at first plane with a thickish margin, then convex and immarginate,
slightly pruinose; hypothecium very thick, brownish-black, with
a paler brown stratum below; paraphyses coherent, brown at
the apices; spores elongate-cylindrical, small, 11-12 (.L long, 4-5 (.L
thick or rather larger; hymenial gelatine palish-blue-violet with
iodine.-Leight. Lich. Fl. cd. 3, 247.
Hab. On stone walls in upland districts.-B. M. Moel-y-gest, neal
Tremadoc, C'arnarvonshire.
18u. L. fuHginosa 'ray!. in Mackay FJ. Hib_ ii. 131 (1836).­
Thallus dark-brown or reddish, granular-squamulose, conglomerate
(K -, CaCI -), with a blackish-brown byssoid hypothallus.
Apotheria black, small, solitary or aggregate, somewhat
convex, with a thin disappearing margin; hypothecium thick,
brownish-black; paraphyses coherent, yellowish-brown, and
brownish- or bluish-black at the apices; spores ellipsoid, smail,
8-10 [J. long, 4-6 [J. thick; hymenial gelatine, especially the asci,
bluish with iodine.-Mudd Man. 208; Cromb. Lich. Brit. 77;
Leight. Lich. Fl. 255; cd. 3, 247. L. conjusa Ny!. Lich. Scand.
216 (1861).
Exsicc. Leight. n. 305.
The thallus is somewhat variable, as the squamulose granules may
be either congested or scattered. The hypothallus is mainly composed