LECANORA| LECANORACEX: 317 
67. L. intermutans Nyl. in Flora lv. p. 354 (1872).—Thallus 
determinate, deeply cracked-areolate, whitish- or brownish-grey 
(K+yellow then rusty-red, CaCl—). Apothecia immersed, the 
dise concave, blackish, the thalline margin prominent, entire, 
becoming inflexed; paraphyses_ slender, moniliform-septate 
upwards ; spores usually 8 in the ascus, 23-34 pw long, 9-15 p 
thick ; hymenial gelatine bluish then wine-red with iodine.— 
Cromb. in Grevillea xix. p. 57 (1891) & Monogr. i. p. 164. 
Differs from the preceding species in the larger spores and, accord- 
ing to Nylander, in the smaller spermatia (7-9 » long, 1 » thick). In 
the single specimen in the British Museum the spores measure about 
20 » in length, and contain two large guttule. The species is recorded 
from the Pyrenees and from N.W. France. 
Hab. On schistose rocks in a maritime district—P. M. Near 
Kylemore, Connemara, Galway. 
68. L. alpina Sommerf. Suppl. Fl. Lapp. p. 91 (1826).— 
Thallus indeterminate, deeply cracked into rounded or angular 
somewhat warted areole, grey or leaden-greyish on a black 
hypothallus (K + yellow then red, CaCl —, medulla I + blue). 
Apothecia numerous, immersed then superficial, the disc plane, 
reddish or black, the thalline margin prominent; paraphyses 
septate, clavate and brown at the tips, with a deep brown line 
over the apex; spores ellipsoid, 9-13 pw long, 6-8 yp thick ; 
hymenial gelatine blue with iodine.—Cromb. in Grevillea xix. 
p. 57 (1891) & Monogr. i. p. 468 (non Leight. in Grevillea i. 
p. 125 (1873)). L. cinereo-rufescens Cromb. Lich. Brit. p. 55 
(1870) (non Nyl.); Leight. Lich Fl. p. 211; ed. 3, p. 197 (non 
Nyl. fide Cromb. Monogr. i. p. 468, note). 
Differs from: L. cinerea in the much smaller spores and the blue 
reaction of the medulla with iodine, a peculiarity shared by L. cinereo- 
rufescens. Spermogones have spermatia 4-6 » long, and about 1 p 
thick. L. Myrini Nyl. (Leight. Lich. Fl. ed. 3, p. 173) is not British. 
Hab. On a mica-schist rock in an alpine situation.—B. M. Ben 
Lawers, Perthshire (the only British record). 
b. Thallus white or whitish-grey, K—. 
69. L. calearea Sommerf. Suppl. Fl. Lapp. p. 102 (1826).— 
Thallus effuse or distinctly determinate, often wide-spreading, 
smooth or farinose, continuous or cracked-areolate, chalky- or 
greyish-white, sometimes greenish at the circumference (K—, 
CaCl—). Apothecia generally crowded, immersed, small, 
irregular in form, becoming plane, the disc black, whitish- 
pruinose, the thalline margin entire or wrinkled ; paraphyses 
loosely coherent, slender, septate, more or less moniliform at the 
tips, the epithecium dark-brown ; spores ellipsoid or subglobose, 
with a thick epispore, 18-30 p» long, 14—27 p» thick ; hymenial 
gelatine blue with iodine.—Cromb. Lich. Brit. p. 54 & Monogr. i. 
p. 473; Leight. Lich. Fl. p. 209; ed. 3, p. 192 (incl. f. conereta). 
