LICHENS AND LICHEN. PARASITES

100 B.A.N.Z. ANTARCTIC RESEARCH EXPEDITION
cells up to 2r in cliametcr, which terminate the m,edullary hyphae, with, a thick layer of dead cells
on the surface up to 4OP thick; algal layer up to 10OP thick, of protococcoid cells up to lor in
diameter; medulla up to 1,20OP thick, of reticulately arranged hyphae up to 2p in diameter, more
01. less vertical tolvard the base of the areolae; 1 ower cortex not differentiated.
Apothecia up to 1.5 mm. in diameter, round or angular from, mutual pressure, convex to
pulvinate, immarginate, gregarious, black, constricted at the base, subsessile to snbstipitate on the
areolae; parathecium of a few cells which merge laterally with the marginal cortex; hypothecium
up to 10OP thick, extending irregularly into the medulla, occasionally as much as 450p, of dark
fnscous brown cells, about 2r in diameter, more or less parallel and vertical ; thecium up to 7OP
tall ; paraphyses 1-1.5,.~, expanding to heads 3-4r in diameter which are hyaline but incrusted
with carbonaceous fragments, unbranched or branched, thick-walled, septate, epitheciuln about
lop thick, carbonaceous, surface irregnlar, K greenish; asci 25-42 X 8-12p, attenuate below,
inflated abruptly above, 8-spored; ascospores s~lbfasciculately arranged, unicellular, hyaline,
6.5-7.5 X 1-7-5!.5p, ellipsoidal, one end sometimes pointed.
This species seems to be quite abundant in our region, but unfortntiately I have been unable
to find mature asci and ascospores, so that it is with much hesitation I have referred it to L. cancriforntis.
In our material the thallus is slightly better developed with some verrucae as large
as the smaller apothecia, and slightly brownish. The algal layer is much thinner, only 2OP thick or
completely n~issilig over large areas, as if the plants were moribund. In the more completely
moribund apothecia, the whole spongy medulla becomes deep brown.
On rocks with Umbzlicaria Hunteri, Lecanora ers~tlans, L. Johnstoni, Candelariella cerebrifo~*ntis,
Alec toria congesta and [Jsnea sp.
King George V Land: Aurora Peak 1,860 ft., A.A.E. 14-1; near Cape Denison, A.A.E.
104-1, 125, 126, 127, 128, 129, 130,131, 1,055.
MacRobertson Land : Cape Bruce B.A.N.Z.A.R.E. 1084, 108-5.
LECIDEA MCLEANI Dodge, sp. nov.
Type: King George V Land : Aurora Peak, 1,860 ft., A. L. IhfcLean, A.A.E. 91.
Thallus 75OP crassitudine, subsquamulosa, squamulis circiter 1 mm. diametro, cinnamomeoalutaceis,
marginibus lsevibus vel subcrenatis; cortex fastigiatus, 2OP crassitudine, hyphis pachydermeis,
conglutinatis, septatis, parte extera gelifacta; stratum algarum ad 220r crassitudine,
cellulis 641p diametro cystococcoideis, in coloniis parvis, subverticaliter dispositis; medulla hyphis
tenuibus pachydermeis, substrato algarum dense contexta, subtus laxius.
Apothecia primum immersa dein elevata, ba si constrictaque, disco nigro, plano vel convexo,
margine concolore, non elevato ; parathecium circiter 5OP crassitudine, cortice fastigjato 30r, crassitudine,
hyphis tenuibus nigris, conglutinatis, medulla subhyalina, 20p crasstitudine, hyphis 3r
diametro laxe contextis; hypothecium 150-15OP crassitudine ad margines tennescens, fuscum,
pseudoparenchymatic~~m, cellulis leptodermeis subsphaericis circiter 4-5r, diamctro; thecinm
5OP altitudine; paraph~.ses tenues, repetito-dichotomi super ascos, celliilis apicalibus sphaericis,
4p diametro, nigris; asci 25 X 8-gP, clavati vel subcylindrici, dein late ellipsoidei, stipite longo;
ascosporae 8nae, amerosporae, pachydermeae, hyalinae, ellipsoideae, circiter 8 X 4p.
Thallus more than 750r thick, subsquamulose, squamules about 1 mm. in diameter, cinnamon-buff,
margin smooth or slightly crenate, closely applied to the rock; cortex fastigiate, about
2OP thick, of thick-walled, conglutinate, septate hyphae, the outer half gelified and structureless
where exposed to the weather; algal layer up to 22OF thick, cells 6--8r, cystococcoid, io small
colonies in more or less vertical rows, with' occasional colonies surviving below the hypothecium
of young apothecia; medulla of slender, thick-walled hyphae, compactly woven below the algal
layer, becoming very loose below, with occasional surviving algal cells deep in the medulla.