LICHENS AND LICHEN. PARASITES

I
DODGE-LICHENS AND LICHEN PARASITES 235
apotheeiis, cellulis sphaericis protococcoideis, 18-22p diametro; medulla laxe contexta, hyphis
hyalinis, leptodermeis, ramosis, 5p diametro; cortex inferior 35-40p hyphis snbverticalibns, lase
contextis, cellulis plus minusve isodiametricis.
Apothecia ad 1 mm. diametro, ad marginem thalli sessilia basi constrict& ad centrum niagis
el~vata, stipitibus ad 2 mm. altitudine, margille laevi, elevato, incurvo, disco concavo dein plano.
badio; cortex amphithecialis ca. 75p crassitudine ei thallo similis; parathecium ea. 35p crassitudine,
hyphis tennibus, pachydermeis, dense contexta, verticalibus ad latera thecii, ca. 3p diametro;
hypothecium ca. 10p crassitudine hyphis leptodermeis: thecium ca. 75p altitudine; paraphyses
tennes dichotomae, apicibns cellulis sphaericis 4~ diametro, epitheeium flavum 20p crassitncline;
asci ca. 50 )( 12p, clavati dein magis ellipsoidei, apicibns incrassatis; ascosporae hyaliuae, ellip-
:.oideae, polari-biloculares, 10 X 4.5.~
Thallns fragmented in removal from rotten granite, subfoliose, centre apparently continnous,
margin lobed, lobes dichotomous, about 1 mm. long, 0.3-0.4 mm. wide, tips furcate, very convex,
flame scarlet to Mars orange ; upper cortex 45-50p thick, pseudoparenchymatous, cells spherical or
nearly so, 6-7p in diameter, arranged in more or less vertical rows; algal layer about 100p thiclr,
np to 200~ thick under the apothecia, cells spherical, protococcoid, 18-22p in diameter; medulla of
loosely IToven, hyaline, thin-walled, branched hyphae, 5~ in diameter; lower cortex 3510p thiclr,
of subvertical, loosely woyen hyphae with more or less isodiametric cells, somewhat gelified,
especially the outer lop, yellowish in section.
Apothecia up to 1 mm. in diameter, sessile and constricted at the base near the niargin, more
elevated with stipes 2 mm. tall near the centre, margins smooth, elevated and slightly inrolled
when young with concave disc, becoming even with the plane, burnt sienna disc at maturity, densely
crowded, covering practically the whole thallns except the marginal zone, somewhat angular from
mutual pressure; amphithecial cortex about 75p thick, similar in structure to that of the thallns,
medulla reaching the level of the hypothecinm at the margin, algal layer under the parathecium ;
parathecinm about 35p thick, of slender, thick-~vall~d, demely woven hyphae about 3p in diameter,
becoming vertical beside the thecium; hypothecium about lop thick, of deeply staining thinwalled
hyphae forming a transition zone between parathecium and thecium; thecinm about 75p
tall; paraphyses very slender, upper half repeatedly dichotomous, tips of about three spherical
cells 4p in diimeter, heavily incrusted with yellow crystals, forming a yellow epithecinm about
20p thiclr ; asci about 50 X 15, clavate becoming more ellipsoidal, tips som2what thiclteaed when
yonng heroming thin at maturity ; ascospores hyaline, ellipsoidal, 10 X 4-5p, protoplasts snbspherical,
4p in diameter, connected by a narrow isthmus.
The material from King George V Land is more fragmentary and srnaller in most dimensions,
bnt seems to be this species.
King George V Land : Horn (Dreadnought) Bluff, A. L. McLean A. A. E. 31-2, 33; Cape
Denison, A.A.E. 1,053.
Queen Nary Land : Possession Nunatak, C. T. Harrisson, A.A.E. 77, type.
XANTHORIA Th. Fr.
Xsnthorz'a Th. Fr., Nora Acta R. Soc. Sci. Upsal. 111, 3, 166; 1861 [Lich. Arctoi].
Pnrntelia sect. Xanthoria Fr., Syst. Orb. Veg., 243; 1825.
Physcia Korb., Syst. Lich. Germ., 90; 1854 non alior.
Ph,yscia sect. Xanthoria Jatta, Syll. Lich. Ital., 148; 1900.
Anaptychia sect. Hynlopolarididymae Hue, Ann. Myc., 12, 517; 1914.