A Revision of the Western Australian Species of Triodia R.Br. 17 
a distinct species. It is described herein as T. angusta. T. Cun ninghamii 
Benth. is not a satisfactory species. It was based on a specimen collected by 
Cunningham in the Cambridge Gulf, on the extreme northern coast of Western 
Australia. The specimen was seen at Kew and consisted of a few bare culms 
and a rather battered panicle most of whose glumes were empty. Neither 
the description nor the key characters are sufficient to distinguish it from 
T. pungens. Specimens collected on the 80-mile Beach by the author agree 
closely with the description but, with others, they grade into T. pungens. 
Bentham’s name is accordingly regarded as a synonym in this paper. 
Brown’s species T. procera and T. microstachya were collected on the 
Upper Victoria River by Mueller. Gardner (Enum. P1. Aust. Occ. 1930) ac- 
cepted these as Western Australian. However the locality belongs to the 
Northern Territory so pending their collection in this State they cannot be 
included in this paper. Brown’s remaining species T. irritans was also recorded 
for the State by Gardner (l.c.) who has collected it from several localities. 
T. Mitchell) Benth. was recorded by Gardner (l.c.). However Queensland 
material, which had been compared with the type material, was made avail- 
able through the courtesy of Mr. S. T. Blake, of the University of Queensland. 
This showed that our specimen was not T. Mitchelli but a variation of T. 
pungens. 
Other species which have been described since the publication of the 
Flora Australiensis include T . Basedowii Pritzel (Fedde, Repert. xv. 356 : 
1918). T. lanigera Domin ( Journ . Linn. Soc.- Bond. xli. p. 278: 1912) and 
T. longiceps J. M. Black {Trans. Roy. Soc. S. Aus. liv. 59: 1930). The most 
recent publication is T. Wiseana C. A, Gardner {Journ. Roy. Soc. W . Aust. 
xxvii. 166 : 1942). 
T. intermedia Cheel ( Svensk Vet- A had. Handb. U.S. lii. No. 10. 4. 1919) 
does not belong in this genus. 
Four new species are described herein. 
Generic Description. 
Spikelets arranged on capillary or short peduncles or more or less sessile 
and secund on lateral branches of the panicle. Spikelets ovate to linear, 
3-20 florets of which the upper two or three are empty and sterile. Glumes 
equal or almost so, scarious or indurate ; 1-13 nerved ; obtuse, acute, acum- 
inate or aristulate ; nerves often obscure ; glabrous or scabrid. Lemmas 
tridentate with nerves in throe groups each consisting of three to seven nerves 
or reduced to three nerves with or without vestiges at their bases. The 
entire portion scarious, hardened or becoming yellow horny-indurate, glabrous 
or pubescent. The lobes either mere indentations of the apex, in which case 
the midlobe may be formed of the prolongation of the central nerve, or there 
may be three scarious or rigid lobes as long as or longer than the entire portion. 
In the former group the nerves are distinct in the entire portion of the lemma, 
in the latter they are very obscure in the entire part and conspicuous in the 
lobes owing to associated strands of chlorenchymatous tissue. Palea shorter 
than the lemma, usually about as long as the entire portion ; the nerves may 
be scabrid and prominent or with a thin membranous wing. Lodicules two. 
cuneate or obovate. Stamens three. Anthers oblong or lancelate, in some 
species dehiscing through subapical slits. 
Perennial, xerophytic tussock-forming grasses. The tussocks may be up 
to two metres in height and the same in diameter. The growth form may be 
discoid, pyramidal or annular duo to the dying away of the central portion. 
