CLIII. GRAMINE^E. 1911 



81. TRIODIA, R. Br, 



(Flowering glumes often 3-toothed.) 



Spikelets several-flowered, paniculate, the rhachis articulate above the outer 

 glumes and between the flowering' ones, hairy round them or glabrous. Glumes 

 unawned, 2 outer empty ones acute, keeled, glabrous or the keel scabrous-ciliate. 

 Flowering glumes usually shorter, unawned, the lower part rounded on the back, 

 more or less .S-nerved at first, often hardened and nerveless in fruit, with 

 8 terminal 1 or 3-nerved lobes or teeth, Palea about as long as the entire part 

 of the glume, with 2 prominent nerves. Ovary glabrous. Styles very short, 

 distinct. Grain somewhat dorsally compressed, enclosed in the glume and palea, 

 free from them. 



The Australian species are all endemic. 



Leaves very pungent, the sheaths usually viscid. Flowering glumes 



silky-oiliate, divided nearly to the middle into 3 lobes. 

 Panicle loose and spreading. Spikelets dark, ^in. long, 8 to 12- 



flowered 1. T. Mitchelli. 



Panicle narrow and dense. Spikelets pale-c lored. 3 to 4 lines long, 



about 6-flowered 2. T. pungens. 



Panicle long narrow and dense. Spikelets pale-eoloured, very numerous 



under 3 lines long, about 3-flowered 3. T. Cunninghamii. 



Leaves very pungent, the sheaths not viscid. Flowering glumes silky- 

 villous at the base, with 3 sets of 3 rerves each, leading to 3 small 

 obtuse teeth , . . . .... 4. T. irritans, 



1. T. Mitchelli (after Sir T. Mitchell), Benth. Fl. Austr. vii. 606. Warrego 

 Spinifex. Leaves very nearly those of T. pungens but longer, nearly terete, 

 pungent pointed, with viscid sheaths. Panicle very much looser, 3 to 4in. long, 

 with capillary branches more or less spreading, the lower ones 1 to l^fcin. with 

 8 or 4 pedicellate spikelets, the upper ones short with 1 or 2 spikelets. 

 Spikelets dark-coloured, |in. long when fully out, ovate or oblong, with. 8 to 12 

 flowers. Outer glumes 3-nerved, obtuse or minutely 3-toothed, about 3 lines 

 long. Flowering glumes 2^ lines long, 3-nerved, the entire part densely silky- 

 villous and at length somewhat hardened, the 3 acute rigid glabrous lobes as 

 long as the entire part or the central one rather longer. Palea glabrous. — T. 

 ■pungens, Lindl. in Mitch. Trop. Austr. 340, not of R. Br. 



Hab.: On the Maranoa, Leichhardt ; near Mount Pluto, Mitchell ; Warrego and Georgina. 

 This species is at times badly infested with Ustilago segetum, £ull. 



2. T. pungens (pungent), /?. Br. Prod. 182; Benth. Fl. Austr. vii. 606. 

 A rigid scrubby more or less glutinous grass, creeping or decumbent and 

 brandling at the base, the flowering stem 1 to 2ft. high. Leaves narrow, 

 convolute, rigid, very acute or pungent-pointed, usually 3 to 6in. long. Panicle 

 3 to 6in. , long, narrow and almost spikelike, the lower erect branches 

 rarely lin. longi Spikelets 3 to 4 lines long, pale-coloured, with about 6 

 flowers. Outer glumes glabrous, acute, under 3 lines long. ^ Flowering glumes 

 rather shorter, the entire base broad, with long silky hairs at the base and 

 margins, but few on the back, hardened and almost nerveless in fruit, the 3 

 lobes broad, glabrous, rigid, acute, nearly as long as the entire part, and each 

 one more or less distinctly 3-nerved in the centre. Palea as long, the 2 nerves 

 or keels very prominent or narrowly winged. — Bestuca viscida, F. v. M. Veg. 

 Chath. Isl. 59, Fragm. viii. 129. 



Hab.: Islands of the Gulf of Carpentaria, R. Brown, Henne. 



3. T. Cunninghamii (after A. Cunningham), Benth. Fl. Austr. vii. 606. 

 Leaves 2ft. high or more. Leaves convolute and rigid with the sheaths more or 

 less viscid as in T. pungens, but much longer, and in one specimen the lower 

 sheaths are eiliate with long silky hairs. Panicle narrow, dense, from a few 



