LICHENS AND LICHEN. PARASITES

DODGE-LICHENS AND LICHEN PARASITES i 1
Tllallus small, umbilicate, dark olive, surface dull, 75r, thick over the central portion thiniling'to
about 5OP at the margin; upper and lower cortex 8-lor, thick, of about two layers of isocliametric
somewhat angular cells; rest of the thallus a gel filled by filaments of Nostoc and hyphae
eonfined to strands between the colonies of Nostoc (reminding one of conditions in the byrenopsiclaceae)
; rhizinae over the central portion of the thallus, margins nude, composed of very long,
thick-\\-allecl septate hyphae 110-120 X 4r,. Apothecia not seen.
I hare hesitated to describe this sterile, sumewhat fragmented g.1-oup of thalli. At first'I
tholight they inight belong it1 the section Mulloti~rrr~ of T,cptogium, but in all but onc of the
:;pcc.ies of that section which I have seen, the cortex consists of a single layer of isodiametric
cells as is general in that genus except in section I-'seudoleptogicin~ (where lower cortex is filaiue!itous)
an? IIon~dknt (where whole thallus is pseudopareiichymatous). Physma is mucll
inore common in Australasia. Krempelhuber (Reise Novara 128, 1870) lists Leptogium (Mal,
lotiwm) Bwrgessii (Lightf.) Mont., a Scottish species, from St. Paul without description.
Growing over mosses and old thallus of Steinern glazccella along with itllykotoblastus stephamodes.
Iiergueleii: near Port Jeanne d'Arc, 1,400 ft., B.A.N.Z.A.R.E. B200-2.
HEPPIACEAE.
Thallns squamose, microphylline to almost f ruticose, with a well developed hypothall;s, with
rhizinae or with a central holdfast; homoeomerous, or more or less heteromerous, mostly of large-
celled pseudoparenchyma ; algge Myxophyceae. Apothecia immersed in the thallus, parathecium
little developed ; paraphyses simple ; ascospores hyaline, unicellular to muriform, ellipsoidal to
spherical; spermatiophores not septate, spermatia short, straight.
HEPPIA Naeg.
Heppiu Naeg. in Hepp, Flecht. - Enr., 49; 1853. nom. nud.: in Mass., Geneac. Lich., 7; 1854.
Type : Heppia zirceolata Naeg. in Hepp.
Thallus subfoliose, closely adherent to the substrate, somewhat imbricate, homoeomkrous,
pseudoparenchymatous, with colonies of algae in the interstices; apothecia immersed, urceolate ;
parathecium absent or evanescent ; paraphyses unbranched, septate ; asci clavate normally
8-spored (many spored in 'sect. Heterim Vainio) ; ascospores unicellular, hyaline, ellipsoidal to
spherical with thin walls; spermogonia immersed, spermatia ellipsoidal, straight.
A widely distributed genus, mostly in the warmer, dryer areas, not previously reported
from the Antarctic. Our single species belongs in the section Peltule Vainio. In some ways it
also suggests Pernuldia Lynge, &dd. on1 Greenland, 118, 8, 23-25 ; 1937, but the parathecium is
not so highly developed:nor is the symbiont Nostoc.
HEPPIA ANTARCTICA Dodge, sp. nov.
Type : MacRobertson Land : Cape Bruce, B.A.N.Z.B.R.E. B103-3.
Thallus ad 2 cm. diametro, hypothallo alutaceo in locis umbrosis, vel brmlneo-olivacco in
locis insolatis, marginibus laevibus, determinatis, fibrosis, areolis assimilativis 0-1-0-2 mm.
diametro, subsphaericis, ad margines hypothalli subsparsis vel ad 0.5 mm. diametro, snbapplanatis,
cerebriformibusve in centro confertis, albido-alutaceis in locis umbrosis, vel brunneoolivaceis
in locis insolatis; hypothallo ca. 10OP crassitudine, hyphis conglutinatis, fuscis, pschydermeis,
ca. 4p diametro, exteris dilutiorib~~s ; areolae assimilantes jnventute corticatae, cellulis
isodiametricis (ut in Leptogio) , maturitate cortice evanescente ; algae Btiyonema, filamentis ca.
15r, diametro, brevibus, in coloniis parvis, a trabeculis ex hyphis tennibus mcdullaribus separ-