LICHENS AND LICHEN. PARASITES

DODGE-LIGHENB AND LICHEN PARASITES 207
slender, 5-15 mm. long ; cortex 40-50p thick, a palisade of highly gelified hyphae, the gel yellowish
in section, surrounded by a layer of clear gel about 7-5-lop thick; algal cells occurring singly or
in small colonies in the outer portion of the medulla, mostly 5-6p in diameter, occasional cells
larger ; medulla about 180p thick, rather compact in the outer half, especially in the vicinity of the
algae, the inner portion very loose, mostly of nnbranched hyphae radiating from the axis, about 4,~
in diameter; chondroid axis slightly elliptic in cross section, 180 X 165p, of densely woven, conglutinate,
more or less longitudinal hyphae.
Most of our material was preserved in formalin which apparently dissolved part of the gel,
leaving the thalli very hft and flaccid. The above description is largely based on the dry
specimen.
Macquarie Island : B.A.N.Z.A.R.E. 5323 -(-preserved material) ; B.A.N.Z.A.R.E. 1,658 (dry
. -
material).
Usnea subgen. Euwnea sect. Glabratae Motyka, Lich. Gen. Usnea ~tud.'~ono~., 2,483; 1937.
Thallus small, rarely medium, very rarely long, fruticulose and cespitose, quite widely
divergently branched, nude, rarely or frequently ramulose, smooth or indistinctly papillose, never
distinctly tuberculate, glabrous, in the herbarium intensely fusces2ent or persistent stramineous;
cortex commonly thin and papery; medulla lax or dense.
Usnea subgen. Ez~wnea sect. Clab~a~tae subsect. Pycnocladae Motyka, Lich. Glen. Usnea Stud.
Monog., 2,484 ; 1937.
Thallus small and cespitose fruticulose, rarely subpendulous and irregularly ramulose,
,'
sterile, smo5th or indistinctly papillate, ramuli few, quite soft and irregularly scattered. I
USNEA ARIDA Motyka.
Usnea arida Motyka, Lich. Gen. IJsnea Stud. Monog., 2,492 ; 1937.
Type :Australia, Gippsland, Tarvin, Mrs. Manton in Naturhist. ~hfmus. Wien, not seen, but
s bcimens from King Island, Bass Strait, Spong, and New Zealand, Mt. Tararua, John Buchanan,
B
goth ex herb. Stirton in British Museum, so determined by Motyka.
! I:
/ USNEA ARIDA var. .~uscrcn~a Dodge, var. nov.
Type : Macquarie Island, Fehtherbed Flat, Sta. 81a, B.A.N.Z.A.R.E. 531-31.
Thallus mollis, erectus, basi 1 mm. diametro, ramis primariis non divergentibus, internodis
brevibus, secundariis basi constrictis, superne repetito-dichotomis, divergentibus, inferne laevibus,
superne spinulosis, articulis subinflatis, ramis ultimis tenuibus apicibus acutis, subnigricantibus,
spinulossisimis; soredia isidiosa ; cortex ca. 35p crassitudine, hyphis pachydermeis, verticalibus,
cellulis isodiametricis; stratum algarum interruptum, cellulis, 7-locL diametro, laxe dispositis;
medulla laxa, 35-60p, crassitudine, hyphis pachydermeis, laxissime contextis ; axis chondroideus
190p diametro, hyphis conglutinatis, longitudinalibux. Apothecia spermogoniaqua non visa.
Thallus spreading, rather flaccid, erect, base about 1 mm. in diameter, lower branches at acute
angles, upper branches at nearly right angles, intqrnodes short; secondary branches slightly
constricted at the base, repeatedly dichotomously brahched above; surface smooth below, spinulose
above, joints relatively long, very slightly inflated and slightly tapering above ; outer portions of