GRAMINEAE 99 



1.5 mm long, the first and second glumes less than one-half as long as the 

 flowering glume. 



In waste places, roadsides, etc., scattered, fl. all the year; widely dis- 

 tributed in the Philippines. India to China and Malaya. 



2. S. virglnicus (L.) Kunth. 



A rather slender perennial grass with prostrate, creeping stems, the 

 erect or ascending flowering branches 8 to 30 cm high. Leaves close-set 

 2-ranked, spreading, convolute when dry, 1.5 to 7 cm long. Panicles 

 rather dense, spike-like, pale, 5 to 6 cm long. Spikelets about 1.5 mm 

 long, the first and second glumes acute, nearly as long as the flowering 

 glume. 



In open grassy places along tidal streams, Malate, Malabon, etc., fl. 

 June-Sept. Along the seashore throughout the tropics and in some tem- 

 perate regions. 



33. ARISTIDA Linnaeus 



Annual or perennial, slender or coarse, erect grasses, the leaves slender. 

 Spikelets usually in lax panicles, 1-flowered. Glumes 3, the first and 

 second empty, narrow, keeled, persistent, the third narrow, rigid, cylin- 

 dric or convolute, acuminate, the tip produced into a long, 3-partite, 

 naked or feathery awn which is often twisted below the branches. (Latin 

 "awn" in allusion to the awned flowering glumes.) 



Species more than 100 in all warm countries, 3 or 4 in the Philippines. 



1. A. cuminglana Trin. & Rupr. 



A very slender, tufted, glabrous, annual grass 6 to 30 cm high. Leaves 

 filiform, up to J.0 cm long. Panicles purple, open, lax, 5 to 12 cm long, 

 the branches and pedicels capillary. Spikelets purple, long-pedicelled, 

 lanceolate, 3 to 3.5 mm long, the secbnd glume longer than the first, the 

 flowering-glume about as long as the first, the awn slender, 8 to 10 mm 

 long, the lateral arms about one-half as long as the median one. 



In open dry grass lands. La Loma, Masambong, etc., fl. Dec.-Feb.; 

 widely distributed in the Philippines but of local occurrence. India to 

 China; also in tropical Africa. 



34. DIPLACHNE Beauvois 



Tall, tufted, annual or perennial grasses. Leaves flat, narrow. Spike- 

 lets many-flowered, spicately arranged on the slender branches of a simple 

 panicle, the spikes not jointed at the base; rachilla jointed at the base 

 and beneath each flowering glume, not produced beyond the uppermost 

 glume. First and second glumes , empty, unequal, obtuse, thin, 1-nerved, 

 persistent. Flowering glumes several, oblong, 1- to 3-nerved, 2- to 4- 

 toothed at the tips, mucronate or awned. Grain free within the glumes 

 and palea. (Greek "two" and "lobed" in allusion to the toothed or lobed 

 flowering glumes.) 



Species about 15, in most warm regions, one in the Philippines. 



1. D. fusca (L.) Beauv. 



A tufted, rather stout, erect, glabrous grass, 40 cm to 1 m high. Leaves 

 6 to 50 cm long, 6 mm wide or less, flat, scabrid, the sheaths smooth. Pani- 

 cles exserted, 10 to 80 cm long, pale-green, erect or nodding, the spikes 

 numerous, spreading or ascending, alternate, slender, 5 to 11 cm long. 

 Spikelets rather distant, 7 to, 10 mm long, linear, 5- to 8-flowered. 



