502 , LICHENACEI. [PERTUSARIA. 
The verrucs, occasionally very tumid, vary considerably according to the 
number of the ostioles. "These are usually 1, but sometimes 3, 4, 5, or 
even more, appearing like minute, blackish subpapillate dots. 
Hab. On rocks in maritime and mountainous districts—Distr. Rather 
local in S.W. England, N. Wales, the 8.W. Highlands, and the 8. 
Grampians, Scotland, as also in 8. Ireland.—B. M.: Pentire, Lamorna, 
near Penzance, Cornwall; Barmouth and near Dolgelly, Merionethshire. 
Appin, Argyleshire; Craig Calliach, Perthshire. Lambay Island, near 
Cork. 
Form 1. microstictica Cromb.—Thallus sprinkled with short, 
simple, concolorous papille, brownish at the apices.—Lichen 
microsticticus Sm. Eng. Bot. xxxii. (1811) t. 2243. Isidium 
microsticticum Turn. & Borr. Lich. Br. p. 94: Hook. Fl. Scot. ii. 
p. 66; Gray, Nat. Arr. i. p. 774; Sm. Eng. Fl. v. p. 231.—Brit. 
Lxs.: Leight. n. 342. 
A sterile condition analogous to form Westringti of P. conereta. The 
papille, as noticed by Turner and Borrer, J. ¢., are minute, scattered, 
rarely confluent, brittle, and when abraded leave a minute white im- 
pression in the crust. 
Hab. On rocks in maritime and mountainous districts.—Diéstr. Spar- 
ingly in the Channel Islands, N. Wales, and S. W. Ireland. 
Form 2. variolosa Cromb. Grevillea, xix. p. 59.—Thalline 
verruce sterile, transformed into white, pulverulent soredia.— 
Var. 3. variolosa Mudd, Man. (1861) p. 271.—Brit. Has.: Leight. 
n. 341, 
Though looking’ as if distinct, it is only one of those variolarioid con- 
ditions so common in the plants of this genus. 
Hab. On rocks in maritime districts —Distr. Very local in N. Wales 
and the 8.W. Highlands of Scotland.—B. M.. Barmouth and Dolgelly, 
Merionethshire. Barcaldine, Argyleshire. 
16. P. coccodes Nyl. Mém. Soc. Cherb. t. v. (1857) p. 146.— 
Thallus determinate or effuse, unequal, subleprose, rimulose or 
rimose, at times verruculose, whitish, often limited by a dark line 
at the circumference (K+yellow, then deep rusty red, CaCl—). 
Apothecia usually several in scattered subglobose or nodulose 
verruce: the ostioles punctiform, black, slightly prominent; spores 
0,115-140 mm. long, 0,040-60 mm. thick._-Cromb. Lich. Brit. 
p. 59. Pertusaria globulifera var. 3. coccodes Mudd, Man. p. 274. 
Isidium coccodes Turn. & Borr. Lich. Br. p. 89; Sm. Eng. Fl. v. 
p. 280; Gray, Nat. Arr. i, p. 412, Lichen coccodes Ach. Prodr 
(1798) p. 10; Eng. Bot. t. 1511. 
A distinct species, though by some authors mixed up with the 
i agrome from which, apart from the habitat, it is sufficiently separated 
y the characters given. The sterile thallus, which, when more leprose, 
is apt to be mistaken fur Lecanora porella, var. Turneri, is often some- 
what isidioid with the isidia cylindrical, short and simplish. When 
fertile, as it rarely is in the British specimens, the verruce are at times 
as if glomerulose. 
