LICHENS AND LICHEN. PARASITES

148 B.A.N.Z. ANTARCTIC RESEARCH ESPEDITION
in diameter; the wall of compact darlr cells 5-7p in diameter ; spermatiophores branched, about lp
in diameter, tapering at the ends; spermatia 1 X 0 .5~ straight.
Although our material is much smaller, it is evidently at the same stage of development as
spermogonia are also present, and it agrees well microscopically. In some plants the layer of dead
cells is almost absent, in others up to 55p thick. Perhaps the small size is due to severer climatic
conditions.
There seems little except size, colour of upper surface and amount of cracking in the upper surface
to separate var. subvirginis (Frey & Lamb) Dodge, n. comb. (U. antarctica v. subvirgimis
Frey and Lamb, Trans Brit. Myc. Soc., 22, 272; 1939).
Queen Mary Land : David Island, C. F. Harrisson, A.A.E. 55, 66, 68, 69 ; Possession Nnnatalr.
C. F. Harrison, A.A.E. 62-2.
UMBILICARIA HUNTERI Dodge, sp. nov.
Type : King George V Land, Cape Denison, J. G. Hunter 21, A.A.E. 21.
Thallus monophyllus, 2-3 cm. diametro, superficie superiore reticulatim scrobiculatus, ad
marginem subcerebriformis, rimoso-aerolatus, statu humido ochraceus vel fulvus, sicco centro
bubalinus, ad marginem griseo-sepiaceus vel obscurior ; superficie inferiore nigro, opaco, nigroruinoso,
laevi, sine rhizinis; cortex superior 50-100~~ crassitudine, strato extero 18-20p crassitudine
obscure brunneo, parte reliqua hyalino, fastigiatus, strato amorpho ad 35p frequenter tectus ;
stratum algarum ca. 35p crassitudine, cellulis 7-8p diametro, protococcoideis, in coloniis parvis
dispositis; medulla ca. 185p crassif~tdine inter reticulationes, hyphis plus minusve periclinalibns,
pachydermeis, 4-6p diametro, lare contextis, strato infero compactius contexto, etiam periclinalibus
sed hyphis superis perpendiculariter dispositis; cortex inferior 18-2OP crassitudine, fastigiatus,
cellulis isodiametricis circiter 7p diametro, obscure brunneis vel nigris. Apothecia spermogoniaque
non visa.
Thallus monophyllous, 2-3 cm. in diameter, upper surface shallowly and finely reticulatescrobiculate
to somewhat cerebriform near the margin, rimose areolate, between yellow ochre and
buckthorn brown when moist, drying pale pinkishbuff at the centre, shading to hair brown or darker
at the crenulate margin ; below black, dull, black-pruinose, smooth, without rhizinae ; upper cortex
50-100$ thick, the outer 18-20p deep brown, the rest hyaline, fastigiate, covered by a layer of dead
cells of variable thickness, often 35p thick; algal layer about 35p thick, cells 7-8p, protococcoid,
often in small colonies; medulla about 185p thick except at the reticulations, of more or less periclinal
hyphae, thick-walled, about 4-6p in diameter, loosely woven, the lower 35p very compact, also
periclinal but running at approximately right angles to the hyphae of the upper portion (hence
showing as cut ends in sections) ; lower cortex 18-20p thick, a palisade of ikodiametric cells, cutting
off spherical cells 7p in diameter, darlr brown to black. Apothecia and spermogonia not seen.
Hunter 11-2 seems to be a young thallus of this species, the cortices being much thinner than
the measurements given above, the thallus is smooth, tawny olive when moist and the medulla has
the same structure as the other specimens cited.
On gneiss with Heppia a.nta.rctica, Toninia Johnstoni, Lecamora emlans, L. Johnstoni,
Thamndecmia Nawsmi and Buellia frigida.
King George V Land : Xiadigan Nunatak, ca. 2,400 ft., 30 miles east of winter quarters, C. F.
Laseron, A.A.E. 2-2 ; Cape Denison, J. G. Hunter, A.A.E. 11-2,21, 22, 123, 128, B.A.N.Z.A.R.E.
B536-18,536-20,536-21,536-22.
UMBILICARIA RUGOSA Dodge & Baker.
Umbilicaria ru.goss Dodge & Baker, Ann. Mo. Bot. Card., 25, 561; 1938.
Type: King Edward VII Land, Roclrefeller Mts., Mt. Helen Washington, P. Siple, F. A. Wade,
S. Corey and 0. D. Stancliff HW12.