RINODINA | PHYSIACEE, 255 
developed thallus. It may however be a depauperate condition of 
that species. 
Hab. On granitic rocks in maritime and inland regions. 
11. R. Bischoffii Koerb. Parerg. Lich. p. 75 (1859).—Thallus 
thin, effuse, continuous and farinose or thinly areolate, greyish 
or brownish, often indistinct (K —). Apothecia very small, 
plane, with a thin entire thalline margin, becoming convex and 
immarginate, dark-brown; paraphyses with clavate branched 
septate and brown apices ; spores broadly ellipsoid, 15-20 » long, 
7-12 » thick.—Psora Bischofii Hepp Flecht. Eur. n, 81 (1853). 
Lecanora Bischofii Cromb. in Journ. Bot. xiii. p. 141 (1875) & 
Monogr. i. p. 399 ; Leight. Lich. Fl. ed. 3, p. 220. 
Distinguished by the minute plane apothecia and the thin scurfy 
thallus. 
Hab. On caleareous rocks in upland situations.—Distr. Rare in 
W. England and the Central Grampians, Scotland.—B. M. Rodmarton, 
Gloucestershire ; Ennerdale, Cumberland ; Craig Tulloch, Blair Athole, 
Perthshire. 
Var. immersa Koerb. |. c-—Thallus immersed in the rock, 
visible as whitish spots. Apothecia immersed-foveolate, minute, 
the brown thalline margin somewhat prominent, otherwise as in 
the species.—Lecanora Bischoffii var. immersa Cromb. in Journ. 
Bot. xiv. p. 360 (1876) & Monogr. i. p. 400; Leight. Lich. FI. 
ed. 3, p. 221. Lecidea alociza Cromb. in Journ. Bot. ix. p. 178 
(1871) (non Massal.) pro parte ; Leight. Lich. Fl. p. 310 pro 
parte. Lecidea alocizoides Leight. Lich. Fl. ed. 3, p. 325 (1879) 
pro parte. Buellia alocizoides A. L. Sm. Monogr. ii. p. 167 
(1911) pro parte. 
Confused with another minute lichen Buwellia alocizoides, as the 
thalline margin is obscure and the spore-characters are not always 
well marked. 
Hab. On caleareous rocks and walls in maritime and upland 
districts.— Distr. Rare in S.W. and N. England and in Wales.— 
B. M. Torquay, Devon; Yatton and Weston-super-Mare, Somerset ; 
Eglwyseg rocks, Denbighshire ; Buxton, Derbyshire. 
12. R. subarenaria A. L. Sm.—Thallus thin, smooth, con- 
tinuous and somewhat uneven or of scattered minute areole ; 
hypothallus blackish-brown, underlying the areole or bordering 
the thallus. Apothecia minute, about 0°3--4 mm. in diameter, 
adnate, plane or concave with a prominent proper margin, 
the thalline margin not visible, but a gonidial layer present 
below the colourless hypothecium ; paraphyses slender, clavate, 
septate, brown and often branched at the tips; asci clavate ; 
spores 8 in the ascus often undeveloped, broadly ellipsoid, polari- 
locular, and sometimes swollen in the middle, the two loculi 
