LECANORA, | LECANO-LECIDEEI,. 469 
The colour of the thallus, as in other similar instances, depends upon 
the presence of peroxide of iron in the substratum. In the British speci- 
mens the apothecia are numerous and at times angulose from mutual 
pressure. Only a few spermogones are visible, with spermatia 0,004-5 
mm. long, about 0,001 mm. thick. 
Hab. On moist mica-schist rocks in an alpine situation.—Distr. Only 
on one of the S. Grampians, Scotland.—B, M.: Above Loch-na-Gat, 
Ben Lawers, Perthshire. 
167. L. recedens Nyl. Flora, 1879, p. 361-—Thallus determinate, 
thick, subverrucoso-unequal, rimoso-diffract, greyish (K—, CaCl—, 
medulla I—). Apothecia small, innate, brownish-black, colourless 
within; the thalline margin slightly prominent ; spores 8ne, sub- 
globose or ellipsoid, 0,009-14 mm, long, 0,007-9 mm. thick; para- 
physes thick, jointed; epithecium brownish; hymenial gelatine 
slightly bluish, then wine-red with iodine.—Cromb. Grevillea, xix. 
p. 57.—Lecidea recedens Tayl. in Mack. Fl. Hib. ii. (1836) p. 117. 
Lecanora subcinerea Nyl. Flora 1869, p. 82; Cromb. Journ. Bot. 
1875, p. 140; Leight. Lich. Fl. ed. 3, p. 197.— Brit. Exs.: Larb. 
Lich. Hb. n. 299 (macrior), 
Well distinguished from the allied species by the subglobose spores 
and the articulate paraphyses. It approaches L. cinereorufescens, but 
from this it differs also in the thicker thallus, the negative reaction of the 
medulla with iodine, and the shorter spores. Our British specimens are 
for the most part well fertile. Though describing it as a Lecidea, Taylor 
i. c. says that it is allied to Urceolaria cinerea. 
Hab, On rocks in maritime and mountainous districts. —Distr. Only in 
N. Wales, N. England, and W. Ireland.—B. M.: Llyn Bodlyn, ‘i 
mouth, Merioneth; Holwick Scar, Yorkshire. Dunkerron, co. Kerry ; 
Derryclare, Connemara, co. Galway. 
168. L. pelobotrya Somm. Lapp. Suppl. (1826) p. 99; Nyl. Lich. 
Scand. p. 155.—Thallus determinate, tartareous, thickish, areolato- 
verrucose, the verruce gibbose or somewhat plane, smooth, crowded, 
whitish (K—,CaCl—). Apothecia moderate, plane, slightly im- 
mersed in the areola, brownish-black; the thalline margin rather 
thick, inflexed; spores 4-8n, ellipsoid or oblongo-ellipsoid, 
0,023-35 mm. long, 0,012-16 mm. thick; hypothecium brownish- 
black or blackish ; paraphyses slender; hymenial gelatine bluish 
with iodine.— Leight. Lich. Fl, ed. 3, p. 195.—Aspicilia pelobotrya 
Mudd, Man. p. 164. Lecedea pelobotrya Cromb. Lich. Brit. p. 80 ; 
Leight. Lich. Fl. ed. 1, p. 298. Urceolaria pelobotryon Wahl. in 
Ach. Meth. Suppl. (1803) p. 31. 
A rather peculiar species of this section, which from the dark hypo- 
thecium might be taken for a Lecidea. The distinct thalline margin, how- 
ever, of the apothecia in well-developed specimens shows that it is a true 
Lecanora. e thallus, which has a whitish evanescent hypothallus, is 
at first plane and continuous, becoming at length thickish and verrucose, 
