Thallus crustaceous, thin or obsolete. Algal cells Trentepolilia.
Perithecia compound with a dark-coloured outer wall (pendimn),
the different perithecia not distinctly separated ; asci ellipsoid ;
paraphyses scanty or wanting ; spores 8 in the ascus, elongate,
septate, colourless or brownish.
1. M. obscurum A. L. Sm.—Thallus thin, forming spots on
the bark. Perithecia compound, thickly scattered over the bark,
orbicular or angular ; the outer peridial wall developed oyer the
top, black, the lower wall colourless ; peritheciai walls indistinct ,
paraphyses scanty, indistinct ; spores 8 in the ascus, oblong-
clavate, 3-septate, halonate, the upper cell slightly larger,
0 015 mm. long, 0,005 mm. thick.— Opegrapha ohscura Pers. m
IJst. Ann. Bot. vii. p. 32, t. 3, fig. 5, B (1794) ; 0. atra yar.
ohscura Schær. Enum. p. 155 (1850) ; Leight. in Ann. Mag. Nat.
Hist. ser. 2, xiii. p. 441, t. 8, fig. 37 (1854). Mycoporum ohscurum
Almq. in K. Svensk. Vet.-Akad. Handl. xvii. n. 6, p. 8 (1880).
Hah. On bark of trees.—R. M. Will’s Braes, Forfar.
2. M. sparsellum A. L. Sm .-T h a llu s white, thin, determinate.
Perithecia compound, enclosed in a black prominent
rugose roundish or irregular peridium, colourless below ; paraphyses
indistinct ; spores 8 in the ascus, ovoid, colourless or
faintly smoky-brown, 1-septate, rounded a t the ends, slightly
constricted, 0,013-22 mm. long, 0,007-10 mm thick.—
porum sparsellum Nyl. in Flora xlvii. p. 618 (1864) & in Ann.
fei. Nat. sér. 5, viii. p. 343 (1867) ; Carroll in Journ Bot. yi.
p. 101 (1868); Cromb. Lich. Brit. p. 106; Leight. Lich. .11.
p. 405 ; ed. 3, p. 437.
Eecorded with several other tropical and sub-tropical species only
from SW . Ireland. The thallus of Lindig’s specunen from
New Granada contains Trentepohlia algæ, which, along with the
septate spores, indicates its position in Myeoporellum.
Hab. On holly.—Distr. Eare in S.W. Ireland (Cromaglown,
Killarney).
There are a number of specimens in the British Museum
classified under the genera Lepraria Ach. (Lioh. Suec. Prod. p. 5
(1798)) Spiloma Ach. (Meth. p. 9 (1803)), and Byssus Mich. (Nov.
Plant Gen. p. 210 (1729) ), which have been specifically determined
by their collectors. These genera and species, generally accepted by
older lichenologists, are the early or imperfect conditions of orus-
taceous lichens, or sometimes of algæ or fungi, most ot them
indeterminable. They grow usually in moist or shady situations
th a t favour irregular growth, while retarding the normal development
of thallus and fruit.
A D D E N D A
P a rt i. p. 88, after C. phaeocephalum.
Calicium roscidum Floerke Deutsche Lich. 3, p. 1 (1815); Nyl.
Syn. Lich. p. 153 (1858-60).—Thallus ashy-grey, thin or almost
obsolete. Apothecia moderate in size, bla ck ish ; stalk black,
rather short and s to u t; capitulum lentiform, the margin or the
entire head greenish-yellow-pruinóse; spores brown or blackish,
fusiform-ellipsoid, 1-septate, slightly constricted a t the septum,
brownish or blackish, 0,009-018 mm. long, 0,004-8 mm. thick.
— Galicium hyperellum var. roscidum Ach. Syn. p. 59 (1814).
Approaches G. phaeocephalum in the size and appearance of the
apothecia, but easily distinguished by the form of the spores.
Hdb. On oak bark.—R. M. Lowther Park, Westmoreland (communicated
by J. A. Martindale).
P a rt i. p. 128, after C. alcicornis.
Cladonia luteoalba Wils. & Wheld. Trans. Liverp. Bot. Soc.
i. p. 7. (1909).—Thallus macrophylline, lobes 5-10 mm. long,
irregularly crenate, yellowish-green above (becoming blackish-
green with age), pallido-sulphureous beneath, th eir apices and
sometimes th eir lateral margins strongly incurved when dry
(as in G. alcicornis) showing th e pulverulent under surface and
rendering the leaflets concave. Podetia rare, only once seen,
short (3-5 mm.), cylindrical, from the surface of the leaflets,
scyphiferous, scyphi hardly dilated, bearing small marginal
discrete scarlet apothecia. The chemical reactions of the upper
face are indistiuct (Kf, C —). The yellow colour of the under
face becomes much deeper on applying caustic potash and the
immediate application of CaClj still fu rth e r intensifies it until it
is of a deep orange-yellow.—See also Journ. Bot. xlvii. p. 324
(1909).
Hdb. On old mosses in high altitudes.—R. M. Graygarth Fell,
Lancashire.
P a rt i. p. 177, after C. sylvatica.
Cladina impexa Harm. Lich. Prance, p. 232 (1907).—Distinguished
by the author from G. sylvatica by the more
swollen main stalks or podetia, the whitish-coloured and sometimes
almost translucent appearance of stalks and branches and