LICHENS AND LICHEN. PARASITES

DODGE-LICHENS AND LICHEN PARASITES 153
somewhat brownish below ; thecium about 90p tall ; paraphyses slender, 1 ~5-2p in diameter, septate,
ending in a two-celled brown club, about 4p in diameter ; asci broadly clavate, tip thickened, protoplast
mamillate, 40 X 12p, tapering below into a stalk about 35p long; ascospores snbdistichous,
2-celled, dark brown, 11-15 X 7-8p, slightly coiistricted at the septum.
On rocks with Umbilicaria rugosa and Leca?tora ezsz~lams.
King George V Land, Cape Denison, B.A.N.Z.A.R.E. 536-16, 536-17, 536-19.
DERMATISCUM HARRISSONI Dodge, sp. nov.
Type: Queen Mary Land, Possessioii Nunatalr, C. T. Harrisson, A.A.E. 56-1.
Thallus super muscos crescens, ca. 1 cm. diametro, crassus, margine crenato, crasso, snperficie
superior laevis aut subverrucosa; strato ainorpho tenuis, ad 18p crassitudi~ie, cortex ca. 70p crassitudine,
fastigiatus, hyphis tennibns leptoclern~eis, conglutinatis, cellulis exteris sphaericis et
obscure bruilneis; stratum algarum non bene evolutum, filamentis Treiltepohlioideis ca. 8p diametro,
inter hyphas verticales medullares, infra emorientibus et inter hyphas corticalibus penetrantibus ;
medulla 100-120p crassitudine, compacta hyphis pachydermeis tenuibus brunneis; cortex inferior
ca. 20p crassitudine, fastigiatus, obscure brunneus.
Apothecia innata, ca. 0.5 mm. diametro, vel in apotheciis compositis ad 1.3 mm. concresceiitia,
disco convex0 immarginata; parathecium carbonaceum, ca. 50p crassitudine, sub hypothecio ad
150p; hypothecium 180-200p crassitudine, parte infera obconica, supra hemisphaerica, flavidum,
hyphis tenuibus, pachydermeis, conglutinatis; thecium ca. lOOp altitudine; paraphyses tenues,
super ascos dichotomi, apicibus clavatis, nigerrimis, conglutinatis, epithecium 8p crassitudine
formantibus; asci clavati vel cylindrici, apicibus incrassatis, protoplasto truncato, uila cum mamilla
magna juventute ca. 55 X 15p ; ascosporae octonae, monostichae vel distichae, brunneae, 2-loculares,
11-18 X 8-lop, septo subconstrictae.
Thallus growing over mosses, about 1 cm. in diameter, thick, margin crenate, thick, upper
surface smooth or somewhat verrucose; amorphous layer thin, up to 18p thick; cortex about 70p
thick, fastigiate, of slender, thin-walled, conglutinate hyphae, the outer cells spherical and dark
brown; algal layer not sharply differentiated, trentepohlioid, filaments abont 8p in diameter,
between the vertical medullary hyphae, dying out below and pushing up between the cortical
hyphae, sometimes to within 20p of the surface; medulla 100-120p thick, compact of slender, thickwalled,
brownish, conglutinate hyphae, more vertical below and passing into the fastigiate, dark
brown lower cortex about 20p thick, from which single, dark brown, thick-walled, septate hyphae,
6p in diameter, serve to anchor the plant to the top of a tuft of decayed mosses.
Apothecia innate at first, about 0.5 mm. in diameter or concrescent in masses 1.3 mm. in
diameter, disc very convex, black, immargiilate ; parathecium carbonaceous, about 50p thick at the.
top of the thecium to 150p or more below the hypothecium ; hypothecium 180-20OP thick, obconic
below and hemispheric above, deep yellow, of very slender, thick-walled, conglutillate hyphae,
becoming increasingly vertical under the thecium; thecium about 100p tall; paraphyses slender,
dichotomous above the asci, tips clavate, very black, conglutinate, forming an epithecium 8p thick;
asci clavate-cylindric, tips thickened, protoplast truncate with a large mammilla when young, 8-
spored, about 55 X 15r; ascospores mono- or distichous, brown, 2-celled, 11-18 X Slop, slightly
constricted at the septum.
Unfortunately this species is represented by a single fragmentary collection, separated from
other lichens, on dead mosses. It is evidently old and weathered, which may account for the browning
of medullary tissue. The species is somewhat aberrant in the genus in being attached to the
substrate by abundant single brown hyphae, rather than by a central hapteron and by much