GKAMINEAE (GEASS FAMILY) 119 



rhachis villous; bristles slender, upwardly barbed, usually 7-12 mm. long: 

 spikelets 2 mm. long ; second glume and sterile lemma equal, covering the obtus< 

 striate faintly wrinkled fertile lemma. — Cultivated grounds and 

 waste places, throughout. (Nat. from Eu.) Fig. 71. Var. bre- 

 VI8ETA (D611) Hitchc. Bristles scarcely longer than the spikelets. — 

 Sterile soil, n. Me. and adjacent Que. 



5. S. itAlica (L.) Beauv. Annual; panicle compound, inter- 

 rupted at base, thick, nodding, 8-20 cm. long, but in escaped speci- 

 mens smaller, yellowish or purplish ; bristles 2 or 3 in a cluster, 

 longer than the spikelets. — Cultivated under the name of Millet, 

 German Millet, or Hungarian Grass, and rarely spontaneous, as 

 is also Var. qekmAnica (Mill.) Eichter, Golden- Wonder Millet, „, „ ,.' . 

 which is more slender and has bristles shorter than the spikelets. gDikelet'x 4 ' 

 (Introd. from Eu.) '^ 



6. S. mdgna Griseb. Probably perennial; culm stout, erect, 1-3 m. high; 

 sheaths loose, spreading, compressed, margins densely ciliate near the summit ; 

 blades 3-6 dm. long, 1-3 cm. wide, attenuate, scabrous ; panicles usually inter- 

 rupted below, 2-6 cm. thick, tapering to both ends ; rhachis densely pilose ; 

 bristles 8-11 mm. long, upwardly scabrous; spikelets 2 mm. long; first glume 

 broad, about | as long as the second, which equals the sterile lemma and with 

 it covers the acute apiculate smooth and shining (not striate nor rugose) fertile 

 lemma. — Low grounds and marshes, Del., Va., and southw. (Trop. Am.) 



15. CENCHRUS L. Sandbur. Bur Grass 



Spikelets 1-ilowered, acuminate, 2-6 together, subtended by a short-pedioeled 

 ovoid or globular involucre of rigid connate spines which is deciduous with them 

 at maturity ; glumes shorter than the lemmas ; sterile lemma with a hyaline 

 palea, fertile lemma and palea less indurated than in Panicum, falcate-acuminate, 

 the lemma not inrolled at the margins. — Our species annual, with simple racemes 

 of spiny burs terminating the culm and branches. (An ancient Greek name of 

 Setaria italica.) 



1. C. carolinianus Walt. Culms flattened, much branched, ascending or 



spreading, 3-8 dm. long ; leaves flat ; racemes of 8-20 involucres, about 8 mm. 



thick, the 6-8 pubescent divisions spine-pointed, 



spines spreading or reflexed ; spikelets 2-3. ( G. 



tribuloides Am. auth. , not L.) — Sandy soil, on river 



banks, etc., s. Me. to Fla., and westw. across the 



continent. Aug. (Trop. regions.) Fig. 72. 



2. C. tribuloides L. Culms more robust, often 



12 C carolinianus xiy, extensively branching or trailing, .3-9 dm. long; 



Closed involucre, at left Longi- sheaths loose, usually hirsute along the margins, 



tudlnal section of same, at right, ligule conspicuously ciliate; blades more or less 



Open spikelet, in middle. involute ; racemes usually included at the base ; 



involucres 12-14 mm. thick, densely long-pubescent ; 



the stout spines spreading or ascending. (O. macrocephalus Scribn.) — Sands 



along the coast, N. J. and southw. 



16. ZIZANIA [Gronov.] L. Water or Indian Rice 



Spikelets unisexual, 1-flowered, the pistillate linear, awned, articulated and 

 tardily deciduous on club-shaped pedicels on the appressed upper branches, 

 the staminate lanceolate, early deciduous, on the expanded lower branches of 

 the same panicle; glumes none in the pistillate spikelet; lemma closely clasp- 

 ing the palea by a pair of strong lateral nerves, a long hispid awn from the sum- 

 mit ; first glume of staminate spikelet 5-, the second 3-nerved ; stamens 6 ; grain 

 cylindrical, 1.5-2 cm. long, closely enveloped in the membranaceous lemma and 

 3-nerved palea. — A tall aquatic grass with long leaves and large terminal paiii- 

 cJes. (Adapted from fijviwoi', the ancient name of some wild grain,) 



