LICHENS AND LICHEN. PARASITES

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DODGE--LICHENS lLND LICHEN PARASITES 209
branched, smooth, or less distinctly grossly papillate or rather verruculose, bone white, shining or
dull and quasi pruinose, fertile or sterile sorediose; cortex comparatively thick and cartilaginous;
. medulla dense, very rarely sublax ; axis rather thick.
Usnea torulosa (Miil1.-Arg.) Zahlbr., Cat. Lich. Univ., 6, 594 ; 1930.
Usnea da.sypvgoides f. toddsa Miill.-Arg., Flora, 66, 19; 1883.
Type: New South Wales, Mt. Kosciuslro, Findley in Herb. Univ. GenBve, not seen, but
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specimen from type loc'ality, Merritt's Camp, J. H. Maiden, Jan., 1899 ; ex Nat. Herb. New South
Wales, seen.
Thallus about 7 cm. tall, erect,f ruMlIose (sirid to be pale green when living), drying wood
brown, and buffy brown when preserved in formalin and alcohol, surface dull, base short, primary
branches about 1-5 mm. in diameter (drying to 1 mm.), slightly attenuated at the base, lower
internodes long between dichotomous secondary branches, cortex with annular cracks, slightly con-
stricted, nearly terete, but somewhat foveolate below, otherwise smooth, eramulose; branches of
upper centimetre, closely dichotomous, ultimate branches rapidly tapering to a blunt tip ; other
secondary branches scarcely tapering but covered with hemispherical soralia, nearly a millimetre
in diameter, producing dense, echinulate isidia, a bout 8-lop in diameter and about 3040p long ;
cortex 90-100p thick, of slender, subvertical deilsely branched hyphae with isodiametric cells
imbedded in a gel; algal layer 35-50p thick, of discrete subspherical colonies of cells about 7-8p in
diameter, rarely up to llp, protococcoid; medulla lax, about 100p thick, of very loosely woven,
thick-walled hypae about 4p in diameter; chondroid axis compressed, almost rectangular in
cross section, about 225 X 140p, solid, of very slender, thick-walled, conglutinate, longitudinal
hyphae.
previously known from &It. Kosciusko, Nea South Wales (the type locality) ; Greymoyth,
New Zealand; and Tasmania, a single collection each.
Macquarie Island, North End, Sta. 81, R.A.N.Z.A.R.E. 540-15; Featherbed Flat, Sta. 81a,b
B.A.N.Z.A.R.E. 531-32.
SECTION LAEVIQATAE.
,I TJsnea subgen. Euusnea sect. Laevigatae Motyka, Lich. Gen. Usnea Stud. Monog., 3,620; 1938.
Thallus variable in size, pendulous or fr~~ticose, mostly white or pale greenish, unchanged in
the herbarium, either very smooth or dull and tartareous, very rarely grossly papillate, nude or
irregularly ramulose, cortex chondroid but soft and fragile, mostly fertile, rarely sorediose.
SUBSECTION ROCCELLINAE.
Usnea subgen. Euusnea sect. I,ap,vigatae subsect. Roccellinae Motylra, Lich. Gen. Usnea Stud.
Monog., 3, 632 ; 1938.
Thallus small, rarely beyond 5-8 cm. tall, fruticose, smooth, tartareous or coarsely papillate,
white, yellowish or even quite dark.
The algae of our species of this group and such others as have been available to me for
examination, are very puzzling. In colonr, shape and tendency to form filaments, they are sugges-
tive of Trentepohlia. On the other hand, in the same section, one sees groups of cells suggestive
of a recently ruptured Trebozlzic (Gystococczcs), afthough there are fewer cells in the group and
the individual cells appear as truncate pyramids (or possibly cones). Other cells of about the
same size, bnt more rounded, are found in the gelified cortex or in the old thecium (after most