LICHENS AND LICHEN. PARASITES

DODGE--LICHENS AND LICHEN PARASITES 263
parvis, dein ellipsoideis, evanescentibus; ascosporae octonae, obscure brunneae vel nigrae, late
ellips~ideae, bilocularibus, septo non constrictae, 8-10 X P5p,, vel unicellulares, sphaericae, ca. 6 ,~
diametro.
Thallus crustaceous, subeffigurate, greyish black; non-assimilating thallus black, areolate iit
the centre, margin thinning out with branched, black strands extending about 0.5 mm. beyond the
areoles; assimilative areoles mostly about 0.2 mm. in diameter, sometimes up to 0.3 mm., 75,~ thick,
pulvinate, circular to somewhat angled or irregular, light olive brown or darker, mostly with
cortex eroded and then dull white; cortex about 20,~ thick, loosely capitate-fastigiate, the terminal
cells larger, thick-walleqand blackened, overlajd by a hyaline amorphous layer 8-lop thick; algae
cystococcoid, up to lop, in\ diameter, scattered tl~rough the loosely woven medulla, resting on a nonassimilative
areole or base, about 200,~ thick, upper half of brownish pseudoparenchyma, lower half
/-carbonaceous,
attached to rock by rhizinal strands about lop in diameter.
Apothecia 0.3 mm. in diameter, round, flat at first, becoming convex, margin smooth, not
prominent, wholly black; immersed in the thallus at first, when it appears bordered by a thin, white
margin, then more elevated; parathecium about 4OP thick, the sides developing late after the
thecium is mature, scarcely differentiated from the non-assimilative areole below; hypothecium
about 35p, thick, of compact, slender, vertical hyphae, hyaline or somewhat greenish black, not
sharply differentiated from the paraphyses above; thecium about 55-6OP tall, greenish in thick
sections; paraphyses slender, repeatedly dichotomous above the asci, ultimate branches about
3-celled, somewhat moniliform, outer cells thick-walled, black, ellipsoid, about 6 X 4p,, forming a
black epithecium 8-15r. thick ; asci clavate, 30 X Sp, when young, tips thickened, protoplast truncate
with a very $mall mamilla, becoming ellipsoid and disappearing when the spores begin to turu
brown, &spored; ascospores darlr brown to black broadly ellipsoidal 2-celled, not constricted at
the septum: 8-10 X P5p, some remaining nnicel!ular, nearly spherical, about 6p, in diameter.
Our material evidently grew in extreme climatic conditions as the cortex has been eroded
from the tops of the assimilative areoles by snow crystals, and a large proportion of the ascospores
appear collapsed and shrunken, as if conditioils had been unfavourable for dispersal when they
matured.
On granite, stained ochraceons below.
King George V Laiid: Rlt. Murchison, 1,860 ft., A. L. McLean, A.A.E. 2.
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BUELLIA MUSCIOOLA Dodge & Baker.
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Buellia mzlscicola Dodge & Baker, Ann. Mo. Rot. Gard., 25, 643 ; 1938.
Type : King Edward VII Land, Rockefeller Mh., Mt. Helen Washington, P. Siple, F. A. Wade,
S. Corey & 0. D. Stancliff, HW-2, HW-10.
Non-assimilative portion 1-75 X 0.7 cm., on rocks or soil among mosses, conspicuous but very
slender, branched, spreading, darlr reddish brown to black, edges of the main strands roughened
by short side branches, of dark, irregular cells; cortex and medulla not differentiated, but tho
inner cells sometimes hyaline; the assimilative areoles up to 0.33 mm. in diameter, pale to red
brown, gelified, especially abundant and prominent at the confluence of the non-assimilative
branches, gregarious or scattered ; cortex soon evanescent ; algal layer protococcoid, abont 601r
thick in the middle of the areole, cells abont 4p in diameter; medulla of loosely woven hyphae,
somewhat more compact under the apothecia ; lower cortex not differentiated ; asexual reproduc-
tion on the non-assimilative portions of the thallus bi bulbils up to 75r. in diameter, spherical,
dark, scattered or in groups, pseudoparenchymatous.
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