POACEAE 107 



the spikelet : spikelets 2 mm. long, ovoid, ucute, the flowering scale acute, abruptly 

 apiculate, transversely rugose. [Setaria imberbis Cliapni.] 



In sandy soil, Texas, and adventive eastward. Also in tropical America. Spring to fall. 



7. Chaetochloa verticillata (L. ) Scribn. Annual. Stems 3-6 dm. tall, erect or 



ascending : leaf-sheaths loose, the margin ciliate above ; blades 7-18 cm. long, 6-12 mm. 



wide, flat, rough on both sides : panicle spike-like : bristles 1-3, stout, Hexuous, 3-6 mm. 



long : spikelets narrowly elliptic-ovate, acute, 2-2.5 mm. long, the flowering scale about 2 



mm. long, rounded at the shortly apiculate apex, smooth, or with very fine transverse 



wrinkles below the middle. [<S'etorta verticillata Beauv. ] 



In waste places, fields and along roadsides, throughout the United States. A cosmopolitan weed. 

 Introduced from Europe. Summer and fall. 



8. Chaetochloa viridis (L. ) Scribn. Annual. Stems tufted, usually much branched 



at the base, compressed, 2-9 dm. tall : leaf -sheaths compressed, loose, ciliate on the margin ; 



blades 3 dm. long or less, 4—10 mm. wide : spike-like panicles 2-10 cm. long, about 1 cm. 



in diameter, exclusive of the bristles, green, the rachis villous : bristles 1-1.5 cm. long : 



spikelets about 2 nun. long, elliptic, the flowering scale elliptic, roimded at the apex, finely 



and faintly transversely rugose below the middle or merely striate and pitted. ^Setaria 



viridis Beauv. ] 



In cultivated groinids and waste places nearly throughout North America. Introduced from 

 Europe. Summer and fall. 



9. Chaetochloa Italica (L. ) Scribn. Annual. Stems simple, or branched at the 

 base : leaf-sheaths loose, glabrous, ciliate on the margin ; blades long-acuminate, 2-4 dm. 

 long, 1.5-3 cm. wide, rough : panicles dense, cylindric, 8-20 cm. long, 2-3 cm. in diam- 

 eter, obtuse or truncate at both ends, the rachis densely villous : bristles 1-3, 3-10 mm. long, 

 often shorter than the spikelets or nearly wanting : spikelets elliptic, 2.5-3 mm. long. 



In fields and waste places, Quebec and Minnesota to Florida and Texas. Widely cultivated and 

 very variable. Introduced from Europe or Asia. The variety C. Italica Gcnndnicd (Mill.) Scribn. 

 differs in being smaller and more slender, and in having a smaller narrower panicle which is usually 

 tapering at the base. Italian Millet. Hungarian Grass. 



10. Chaetochloa magna (Griseb. ) Scribn. Stems stout, erect, 1-4 m. tall, branch- 

 ing at the base : leaf-sheaths glabrous, compressed ; blades 3-6 dm. long, 1-3 cm. wide, 

 rough : panicle usually interrupted below, 1-3.5 dm. long, 2-5 cm. in diameter ; bristles 

 1-3, green, 8-11 mm. long: spikelets elliptic, acute, 2 mm. long. ISetaria magna Gvii^eh.} 



In swamps or even in shallow water, Delaware to Florida, Louisiana, and Texas. Also in tropical 

 America. Summer and fall. 



11. Chaetochloa corrugata (Ell.) Scribn. Annual. Sterns tufted, 5-10 dm. tall, 

 compressed, much branched at the base, sometimes rooting at the lower nodes : leaf-sheaths 

 very loose, compressed, keeled ; blades 1-3 dm. long, 3-6 mm. wide, rough, narrowed to- 

 ward both ends : panicle 5-15 cm. long, 5-15 mm. in diameter, exclusive of the bristles : 

 bristles solitary or rarely 2 at each spikelet, 5-15 mm. long : spikelets ovoid, acute, about 

 2 mm. long, the fourth scale very strongly transversely and coarsely undidate-rugose. 

 l^Setaria corrugata Schult. ] 



In fields and waste places, Georgia and Florida. Summer and fall. The variety C. corniguta 

 parvifldra (Poir.) Scribn. &. Mer. is a more slender and short form with shorter leaf- blades and panicles. 

 In similar situations. South Carolina to Florida. Also in the West Indies. Spring to fall. 



12. Chaetochloa compdsita (H.B.K. ) Scribn. Perennial. Stems tufted, 3-10 

 dm. tall, much branched from the base, usually pubescent : leaf-sheaths compressed, mostly 

 glabrous ; blades linear, flat, 1-3 dm. long, 2-5 mm. wide, glaucous, usually rough : panicle 

 pale green, 5-15 cm. long, 5-15 mm. in diameter, exclusive of the bristles : bristles single, 

 rarely in pairs, green, flexuous, 5-15 mm. long : spikelets narrowly ovoid, 2-3 mm. long, 

 the flowering scale narrowly ovoid, acute. 



In dry soil, Colorada to Arizona and Texas. Also in tropical America. Summer and fall. 



13. Chaetochloa macrostdchya (H.B.K. ) Scribn. & Mer. Perennial. Stems erect 

 or ascending, 6-12 dm. tall, rather stout, compressed : leaf-sheaths loose, glabrous or nearly 

 so; blades linear-lanceolate, rigid, 1.5-5 dm. long, 1-1.5 cm. wide, usually rough, gener- 

 erally with a few long white hairs near the base: panicle pale green, strict, usually taper- 

 ing at the apex, 1-3 dm. long, 1-2 cm. in diameter : bristles single or in pairs, slender, 

 flexuous, 1-2 cm. long : spikelets ovoid-globose, about 2 mm. long, acute, the flowering 

 scale strongly convex, apiculate, transversly undulate-rugose. 



In dry soil, Texas. Also in tropical America. Spring to fall. 



14. Chaetochloa macrosperma Scribn. & Mer. Perennial. Stems stout, 6-12 dm. 

 tall, glabrous : leaf-sheaths compressed, glabrous, the margins ciliate ; blades linear-lanceo- 

 late, 1-3 dm. long, 1-2 cm. wide, rotigli or smooth : panicle 1-2.5 dm. long, 2-4 cm. in 

 diameter, exclusive of the bristles : bristles single, 1.5-3 cm. long, green: spikelets nar- 



