PTERYGIUM. | LICHINEI. 35 
at the circumference, subcoralloideo-multifid or microphylline and 
usually diffracto-globulose in the centre, dark-olive or olive-brownish- 
black, opaque ; lacinie thin, plane, multifid, imbricately crowded, 
obsoletely rugulose. Apothecia small, plane or slixhtly convex, 
black ; spores ellipsoid, 3-septate, 0,015-20 mm. long, 0,006-8 mm. 
thick; hymenial gelatine deep blue with iodine.—Cromb. Gre- 
villea, v. p. 108; Leight. Lich. Fl. ed. 3, p. 12. 
This is externally somewhat like Pannaria triseptata Nyl., but differs 
in the absence of a hypothallus, and in the lacinie being radiate at the 
circumference and usually digitate at the apices; the spores also are 
somewhat smaller. In the only fertile British specimen seen the apo- 
thecia are sparingly present. 
Hab. On schistose rocks in alpine situations.—Distr. Very local and 
scarce amongst the S. Grampians, Scotland.—B. M.: Summit of Craig 
Calliach, Perthshire. 
3. P. Lismorense Cromb. Grevillea, v. (1877) p. 108.—Thallus 
thin, subfurfuraceous, thinly or obsoletely radiate, adnate, variously 
confluent, blackish or olive-black. Apothecia small, thinly mar- 
gined, black, dark within; spores oviform, 1-septate, 0,010-0,011 
mm. long, 0,005—0,006 mm. thick; epithecium bluish-black ; hypo- 
thecium cellular, and (with the perithecium) violet-blackish ; hyme- 
nial gelatine bluish, then dark-yellowish with iodine.—Nyl. Flora, 
1877, p. 221; Leight. Lich. Fl. ed. 3, p. 12.—Brit. Exs: Cromb. 
n. 101. 
The thallus spreads rather extensively, though not continuously, over 
the substratum. In its younger state the radii are more discrete at the 
circumference. It is allied to P. asperellum Nyl., from which it differs 
in the thallus and the smaller spores. 
Hab. On calcareous rocks in maritime tracts.—Dzstr. Local and scarce 
in the 8.W. Highlands.—B. M.: Island of Lismore, Argyleshire. 
11. LEPTOGIDIUM 
Nyl. Flora, 1873, p. 195 
(ofr. Cromb. Grevillea, v. 
p. 76).—Thallus minute, 
fruticulose, branched, 
somewhat fragile; goni- 
mia moniliform; cortical 
layer cellular, distinct. 
Apothecia subbiatorine ; 
spores 8ne, ellipsoid, : 
simple, colourless; hyme- , Fig. 7. a 
nial gelatine bluish with L¢plogidium dendrisowm Nyl.—a. Thalline 
arene Rt branch and branchlet, x 30. 6. Transverse 
iodine. Spermogones no section of a branch, x 200. ¢. Apex of a 
seen rightly developed. bifureate branchlet, showing the moniliform 
. chains of the gonimia, x 200. d. Two 
This genus, recently in- series of gonimia, x 350. 
stituted by Nylander, is 
Da 
