GRAMINEAE 95 



25. CENCHRUS Linnaeus 



Annual or perennial, erect grasses with flat leaves and dense, cylindric 

 spikes, composed of ovate involucres consisting of hardened spines connate 

 below and forming a cup, bristly at the base, enclosing 2 to 6 spikelets. 

 Involucres jointed to the rachis, deciduous. Glumes 4, the first and second 

 empty, the first small, the second shorter than or equaling the third, the 

 third enclosing a palea and sometimes a staminate flower, the fourth char- 

 taceous, enclosing a palea and a perfect flower. Stamens 3. - (Ancient 

 Greek name for Italian millet.) 



A small genus of tropical and some temperate regions, a single intro- 

 duced species in the Philippines. 



1. C. ECHiNATUS L. Cauit-cauitan (Tag.). 



An erect, somewhat tufted, branched grass 0.2 to 0.8 m high, the lower 

 parts of the stems sometimes prostrate and rooting at the nodes. Leaves 

 8 to 30 cm long, 0.5 to 1 cm wide. Spikes dense, cylindric, 3 to 10 cm long, 

 about 1 cm in diameter, involucres 20 to 50 or more, densely arranged, 

 green, about 5 mm in diameter, the spines 2 to 3.5 mm long, the basal, 

 Jbristles numerous. Spikelets about 5 mm long. 



Common in waste places, along roadsides, etc., in and about towns 

 throughout the Philippines; introduced from tropical America. 



26. SCTARIA Beauvois 



Erect, slender or coarse, annual grasses, the leaves flat, the spikelets 

 arranged in dense, cylindric, spike-like panicles,' or the panicles sometimes 

 lax, open, each spikelet subtended by an involucel of from one to -many, 

 slender, persistent, scabrid bristles. Spikelets jointed on the branches, 

 unawned, the glumes 4, the first shorter than the others, the second and third 

 subequal, all thin, the fourth coriaceous or hardened, shining, smooth or 

 rugose, enclosing a palea of similar texture and a perfect flower. (Latin 

 "bristle.") 



Species 25 or 30, temperate and tropical, 5 in the Philippines. 



1. Inflorescence a dense cylindric spike-like panicle. 



2. Bristles few, 1 to 3 at the base of each spikelet..... 1. S. vit'idis 



2. Bristles many &t the base of each spikelet, yelloiy or purplish. 



2. S. flava 



1. Inflorescence a lax, open, few-flowered panicle, bristle one subtending 



each spikelet 3. S. laxa. 



1. S. viRiDis (L.) Beauv. 



A slender, tufted, erect, annual grass, the stems usually branched below, 

 10 to 60 cm high. Leaves 6 to 20 cm long, 2 to 8 cm wide, flat, acuminate. 

 Panicles dense, cylindric, spike-like, 2 to 8 cm long, about 1 cm in diameter, 

 green. Spikelets about 2 mm long, elliptic, the flowering-glume elliptic, 

 faintly transversely rugose or pitted. 



Along roadsides, rare; introduced from America or Europe; widely dis- 

 tributed in the Old World, introduced in America. 



2. S. flava (Nees) Kunth. 



A slender, erect, unbranched, loosely tufted or scattered, annual grass 

 1.3 m high or less. Leaves flat, 10 to 40 cm long, 3 to 7 mm wide. Panicles 



