LICHENS AND LICHEN. PARASITES

156 B.A.N.Z. ANTARCTIC RESEARCH EXPEDITION
Type : U. kergueliensis Tuck.
Thallns crustose, effigurate, the central areoles very convex, almost stipitate, crowded, appearing
cerebriform; marginal areoles short lobate; cortex decomposed ; algae protococcoid; in a thin
layer on the top and sides of the areoles, often disappearing; medulla of slender, loose hyphae in
a dense gel. Apothecia immersed in the aeroles, solitary; parathecium scarcely developed; hypothecium
hyaliile ; thecinm not extending up the. sides of the very urceolate apothecium; paraphyses
slender, flexuous, dichotomously branched, tips acuminate in the thecial gel; asci cylindric,
8-spored; ascospores hyaline, ellipsoidal with a thin sheath.
This endemic genus seems much more closely related to Pertl~saria in the strncture of the
apothecial warts, the slender branched and anastomosing paraphyses and the spores with a thin,
gelified sheath. While the spores are smaller than those of most Pertusariaceae, the protoplast
appears similar and is probably multinucleate.
URCDOLINA KERGUEZ~IENSIS Tuck.
Urceolina kergueliensis Tuck., Bull. Torrey Bot. Club, 6, 58; 1887: Bull. U.S. Nat. Mus., 3, 29;
1876 : Proc. Amer. Acad. Arts Sci., 12,184 ; 1877 : Syn. N. Amer. Lich., 2, 150 ; 1888 ; Bouly
de Lesdaiii, Ann. Cryptog. Exot., 4, 100 ; 1931.
Lecanora kerguelensis Crombie, Jour. Bot. Brit. For., 15, 106; 1877 : Phil. Trans. Roy. Soc.
[London], 168, 49 ; 1879 : Rept. Sci. ResultsVoy. "Challenger" Bot., 1,2,326 ; 1885 : Zahlbr.,
Deutsche Siidpolar Exp., 8,49 ; 1906.
Placodium kerguelense Miill.-Arg., Bot. Jahrb. [Engler] , 5, 136 ; 1884 : Forschungsreise S. M. S.
"Qazelle," 4,ll; 1889.
Type : Kerguelen, Molloy Point, J. H. Kidder (U.S. Transit Venus Exp.).
Thallus crustose, effigurate, up to 6 cm. in diameter, thick, verrucose areolate, the central
areoles heaped, more or less stalked, giving a cerebriform appearance, margin thick, lobes once or
twice dichotomously branched, about 1 mm. broad and about 3 mm. long, very convex, smooth
and shining, mars yellow to ochraceous orange; cortex 35p thick, decomposed from septate peri-
clinal hyphae ; algal layer 25p thick, protococcoid, of closely packed cells about 4-5p in diameter,
covering the tops and sides of the areoles, but discontinuous when the cortex merges imperceptibly
into the medulla; medulla of slender, very loosely tangled hyphae about 2p in diameter, imbedded
in a gel. Apothecia solitary in the thalline warts, wholly immersed, disc punctiform, black, greatly
depressed (more like'a depressed ostiole than an epithecium) ; amphithecium not differentiated;
parathecium about 15p thick, not differentiated from the medulla except more deeply staining
and hyphae more compactly woven, completely surrounding the thecium and hypothecium;
hypothecium 125p thick in the centre, thinning to the edge of the thecium, of densely woven, deeply
staining, slender hyphae; thecium 600p in diameter and 375p tall; paraphyses slender, flexuons,
dichotomously branched and anastomosing, about lp in diameter in the thecial gel ; asci cylindric,
8-spored, 250 X 18-20p, wall gelified, about 4p thick, tip not thickened more than the rest;
ascospores monostichous, ellipsoidal, hyaline 21-30 X 15-20p, sheath thin, sometimes with a small
papilla at one or both ends. Spermogonia immersed in the thalline warts ; wall about lop thick,
of slender, periclinal hyphae, scarcely differentiated from the medulla, but more deeply staining;
spermatiophores in a dense palisade lining the variously folded cavity, about 15-18 X lp;
spermatia acicular, curved, 18-20 X lp.
Wilson, M6m. Herb. Boissier, 18, 88 : 1900 lists Lecanora kergudiensis var. lateritia, mm.
nud. from Kerguelen, Royal Sound, collected by Robert Hall.