26 THE FLORA OS THE NOBTHEEN TEEEITOEY. 



Spikes several, often numerous. Spikelets both pedicellate, 2nd glume 

 with a fine straight awn. Awn of the terminal glume long. 



Annual. Spikes 1| to 2 in. long. — 1. P. articulata. 

 Perennial. Spikes 3 to 5 in. long. — 3. P. irritans. 



Spikes 2 or 3. Spikelet sessile ; 2nd glume not awned. 

 Awn of the terminal glume short and fine. — 2. P. Cumingii. 

 Third glume not much shorter than the second, thin and hyaline. Awn 

 with a narrow hyaline 2-lobed dilatation at the base. — 4. P. Mackinlayi. 



1. P. articulata, Trin. — ^Port Essington, Armstrong ; Port Darwin, 

 Schultz (No. 146). 



2. P. Cumingii, Nees.—QO miles N.E., C. II., G. F. Hill (No. 292), 

 7/6/1911. 



Near Haast's Bluff, Macdonnell Ranges, G. F. Hill (No. 199). Alt., 4000. 

 22/5/1911. Near water. 79 miles N.W. of C. III., in desert west of 

 Lander Creek. G. F. Hill (No. 343), 14/6/1911. Newcastle Waters. G. F. 

 Hill (No. 492), 7/7/1911. Undunya Creek, near Finke River. G. F. Hill 

 (No. 29), 3/3/1911. Grass in creek bed, 4 ft. high. At Black Rocks, 

 MacArthur River. G. F. Hill (No. 650), 22/10/1911. Northern Territory. 

 Gilruth and Spencer. July- Aug., 1911. 



Recorded. Islands of the Gulf of Carpentaria, R. Brown ; Dampier's 

 Archipelago, A. Cunningham ; Port Darwin, Schultz (No. 466). 



3. P irritans Benth. — ^Arnhem's Land, M'Kinlay. 



4. P. Mackinlayi, F. v. M. — ^North Coast of Arnhem's Land, M'Kinlay. 



4a. SPATHIA, EWART. 



Spikes protected by large sheathing bracts which are enlarged bases of 

 foHage leaves. Lamina persists, but is reduced ; it articulates with enlarged 

 base and tends to be deciduous at the articulation. 



Inflorescence consists of one or two empty bracts at the base, and above 

 them are larger bracts which completely surround the clusters of flowers. 

 When young the lowest bracts ensheath the upper, but as the axis elongates 

 they separate. Main axis of each condensed panicle is short, secondary axes 

 are digitate, 3 or 4 at end of main axis. 



Spikelets are arranged in notches on secondary pedicels, 'wdth articulation 

 at each node. Pedicels also branched at each node, and spikelets disarticulate 

 in groups of two. The lower groups bear the stalks of the groups above. 



Spikelets 1- flowered and of two kinds. One is hermaphrodite with four 

 glumes and two lodicules. Outer glume largest, cUiate ; second smaller and 

 more membranous : third reduced, hyaHne ; fourth glume represented by an 

 elongated awn, which is closely appHed to but free from the glume enclosing it. 



The upper spikelet, as far as can be determined, is sterile, but it may 

 possibly be male. No stamens could be found in any upper spikelet. It con- 

 sists of one large outer glume, which completely surrounds a rudimentary 

 membraneous inner glume. 



The styles are distinct. The grain is enclosed in the outer glume, but is 

 free from it. 



Spathia, neurosa. Ewart and Archer, (Plate I.) 



Stems about 1 ft. high ; nodes hairy. Leaves deciduous, lamina having 

 definite articulation, which breaks readily. 



