LICHENS AND LICHEN. PARASITES

DODGE-LICHENS AND LIOHEN PARASITE8 191
The above description is based on onr Macquarie Island material. I have had some
hesitation in referring our material here as it is sterile, but it agrees well with Taylor's original
description. P. tenzcirz'nla and its varieties seem to be common in south-eastern Australia, Tasmania
and New Zealand.
Macquarie Island: north end, Sta. 81, C.A.N.Z.A.R.E. B540; Featherbed Flat, Sta. 8la,
B.A.N.Z.A.R.E. 531-24 : highland, B.A.N.Z.A.R.E. B534-9, B534-10, B53Pll.
PARMELIA JOHNSTONI Dodge, sp. nov.
Type: RIacRobertson Land, Cape Bruce, Sta. 108, B.A.N.Z.A.R.E. B108-16.
Thallus fragilis, lobis tenuibus, radiatis, imbricatis, subdichotome ramosis, apicibus rotundatis,
2-3 mm. latitudine, superficie convexa, laevi, deinde subverrucosa, opaca, viridi madefacta,
olivaceo-alutacea siccitate, K rufescens; soredia in partibus vetustioribus, granulosa, aetate
nigricantia, inferne albidus vel pallide alutacea cum rhiGnis brunneis sparsis; cortex superior
crassitudine variabili 25-45f~, hyphis pachydermeis 4-5~~ diametro, cellulis isodiametnicis
fastigiatus; stratum algarum ad 7 5 crassitudine, ~ cellulis protococcoideis, 7-8f~ diametro ; medulla
130-14OP crassitudine, hyphis pachydermei, 4-5f~ diametro, dense contexta ; cortex inferior
35-4OP, hyphis plus minusve verticalihus, pachydermeis, conglutinatis, cellulis elongatis ; rhizinae
ad 75f~ diametro. Apothecia ca. 1.5 mm. diametro, margiiie inflexo, disco concavo dein plano, fulvo ;
basi constricta ; cortex amphithecii ca. 75.a crassitudine, cortici inferiori similis; stratum algarum
ca. 75f~ crassitudine, sub hypothecio; thecium destructum.
Thallus fragile, lobes narrow, radiate, imbricate, branching more or less dichotomous, tips
rounded, 2-3 mm. broad, surface convex, smooth becoming verrucose, dull, tea-green when moist,
drying olive buff, K rufescent ; soredia scattered on the older portions, coarsely granular, darkening
in age; under side white or light buff, with scattered tufts of brolrilish rhizinae; cortex
variable in thickness, 25-45f~ thick, a palisade of thick-walled hyphae 4-5f~ in diameter with isodiametric
cells, forming a pseudoparenchyma; algal layer about 75f~ thick, with a few scattered cells
deep in the medulla, cdls protococcoid, 7-8,u in diameter, moderately packed, not in conspicuous
colonies; meclnlla 130-140p thick, of compactly woven, thick-walled hyphae, P5f~ in diameter;
lower cortex 35-5OP thiclr, of more or less vertical, thick-walled, conglutinate hyphae, cells more
elongate, hence not appearing as a pseudoparenchyma ; rhizinae about 75f~ in diameter from the
outgrowth of the lower cortical hyphae.
Apothecia about 1.5 mm. in diameter, margin inrolled, disc concave at first, becoming plane,
tawny, constricted beneath; amphithecial cortex about 75f~ thick, similar to ihe lower cortex of
the thallus; algal layer about 75f~ thick, extending under the hypothecium.
All of our material is badly fragmented, whether in formalin or dried, so it has been very
difficult to interpret. The apothecia are all old or very young, with only traces of the thecium
left. Apparently after the thecium disappears, the algae proliferate rapidly to form soredia.
In B108-20, growing over Xanthh Mmusoni, the amphithecial cortex is only 35f~ thick;
parathecium hyaline, about 35p thick, compactly woven of thick-walled hyphae similar to those
of the medulla below the algal layer, thinning to lop at the margin, then expanding flabellately
and merging with the amphithecial cortex and paraphyses; hypothecium 25cr thick, of more or
lessvertical, branched and closely septate hgphae, deeply staining; thecium 55f~ tall; paraphyses
very slender, mostly unbranched, tips clavate, about 3-5f~ in diameter, forming a darlr greenish
epithecium about lop thiclr; asci broadly clavate to subcylindric, tips greatly thickened, protoplasts
acute, becoming rounded above, about 35 X 8f~, 8-spored ; ascospores distichous, unicelli~lar,
hyaline 8-10 X 3-5-4f~.