LICHENS AND LICHEN. PARASITES

very short just above the base, branches ahont 1 mm. in diameter, flexuous, intermediate inter-
nodes much longer, upper internodes shorter, with occasional ramuli (branches with arrested
deyelopment), tips acute, often blackened. opaque (shining wherc the pruina has been rubbed off
in handling), olive ochre or lighter, surface smooth, rarely slightly rugose or verrucose from
unopened soralia which are circular with slightly elevated margins, slightly eroded, sometimes
confluent on the intermediate branches; soredia of a few algal cells in a dense, spherical colony
surrounded by brow11 hyphae, hence appearing as minute black points on the surface of the soralia
wherc pme cf the soredia gelminate in sitzi, forming tufts of short, black ramilli (propagula)
about 0.2 mm. long; cortex about 20p thick, gelified, covered with a thin layer of minute yello~v
crystals, a palisade of branched, thick-walled hyphae with very anal1 lumina ; algal layer about 35r
thick, cells in filaments or scattered, short cylindric, np to Pp ill diameter, usually shorter than the
diameter, isolated cells somewhat less angular, surrounded hy medullary hyphae; medulla 35--25,~
thick, K- or somewhat brownish, hyphae thick-u,alled, 4-5p in diameter, very dense, with very large
hyaline crystals filling the spaces below, slightly looser in the nppcr branches with fewer crystals;
Chondroid axis up to 500p below, circular in cross section, of slender, thick-walled, conglutinate,
branched hypheo, 150-175p in diameter above, less regular in cross section. Spothecia and sper-
mogonia not seen.
The germination of the soredia of the upper soralia in situ, gives the appearance of a minute
witches' broom. These evidently serve as propagula, since they are attached to the parent plant
only by medullary hpphae, their s!ender, chondroid axis not being attached to the chondroid axis
of the parent plant. The algal layer consists of a few flattened colonies, not in a continuous layer.
The tip consists of free ends of the hyphae of the chondroid axis, not covered by cortex nor algae,
as described by Darbishire, Ann. Crypt. Exot., 5, 164; 1932, for U. hereroensis (Vain.) Darb.,
another species of the subsection Roccellinae.
Heard Island : between Atlas Cove and Corinthian Bay, B.A.N.Z.A.R.E. B140-51, B140-52,
type, R140-53, B140-54, B140-55, B140-56, B140-61.
TJSNEA FLORI~RMIS Dodge, sp. nov.
Type: Heard Island, Atlas Cove and Corinthian Bay, B.A.N.Z.A.R.E. B140-1.
Thallus adscendens, rigidus, ca. 6 cm. altitndine, teres, 2 mm. diametro basi, ramis dichotomis,
perpendicularihus, curvatis, ramis ultimis ad 1 mm. diametro, basi decorticatus, superne fulvus,
opacus, sed non pruinosus, dense minuteque tuberculatus, tubercula in sorediis minutis erumpentia,
ramis liltinlis grosse tuberculatis, tubercula in soredia flava, erosa, erumpentia, dein plus
minusve nigricantia ; cortex ad 90p, variabili crassitudine, fastigiatus, hyphis tenuibus ad 2p diametro,
plus minusve superne ramosis, sine crystallis, gelifactns; stratum algarum 150-180p crassitndine,
anrantiacum luce reflexo, viridiflavum luce transmisso, cellulis cylindricis vel subangnlosis,
filamentis ex axi chondroideo plus minusve radiantibus, dein cellulis plus minllsve ab hyphis ca. 4p
diametro medullaribus separatis, circa axem crystallis abundanter nubilatis; axis chondroidens
sectione transversali subellipticus 250 X 350,~ (in ramo secto) diametro, hyphis conglutinatus
longitudinalibns ab funiculis ex hyphis plus mil~usve horizontalibus separatis.
Spothecia sessilia super ramos majores, ad 1 cm. diametro, contorta, margine plus minuwe
inflexa, floriformiter scissa, excipulo eciliato, laevi, subnitido, poris respiratoriis numerosis quae in
apotheciis vctustioribns in soralia orbicnlaria ewsa expandunt, disco concavo, vel irregulari,
obscure brunneo nigricantique; cortex amphithecii 40p crassitudine, fastigiatus, hyphis tennibus
pachyciermeis, dimidia parte superiori cum crystallis subbrunneis, parte inferiori hyalina, paucis
cum crystallis; stratum algarum ca 100,~ crassitudine, cellulis dense dispositis; medulla ca. 150;l