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 em 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 
bristles 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. SETARIA 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. viridis 
2. Bristles many at the base of each spikelet, yellow or purplish. 
2. S. flava 
1. Inflorescence a lax, open, few-flowered panicle, bristle one subtending 
ein SReT. fe Stee WL SS at Bee one Oe sears 3. S. laxa 
1. S. viripis (L.) Beauv. 
A slender, tufted, erect, annual grass, the stems usually branched below, 
10 to 60 cm high. Leaves 5 to 20 cm long, 2 to 8 cm wide, flat, acuminate. 
Panicles dense, cylindric, spike-like, 2 to 8 em long, about 1 cm in diameter, 
green. Spikelets about 2 mm long, elliptic, the flowering-glume elliptic, 
faintly transversely rugoSse 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 
