1 68 



GRAMINEAE. 



Vol. I. 



24. ZIZANIA L. Sp. PL 991. 1753. 



A tall aquatic monoecious grass with long flat leaf-blades and an ample panicle. Spikelets 

 i-flowered, the pistillate borne on the upper branches of the panicle, the staminate on the 

 lower. Scales 2, membranous, the outer somewhat longer, acute in the staminate, long- 

 awned in the pistillate spikelets. Stamens 6. Styles nearly distinct. Grain linear. [From 

 an ancient Greek name for Darnel.] 



A monotypic genus of North America and Asia. Type species : Zizania aquatica L. 



i. Zizania aquatica L. Wild Rice. Indian 

 Rice. Water Oats. Fig. 399. 



Zizania aquatica L. Sp. PI. 991. 1753. 



Zizania palustris L. Mant. 295. 1771. 



Culms erect from an annual root, 3°-lO° tall, 

 smooth and glabrous. Sheaths loose, glabrous; 

 ligule about ¥ long, thin-membranous ; blades 1° or 

 more long, i'-ii' wide, more or less roughened, 

 especially above, glabrous; panicle i°-2° long, the 

 upper branches erect, the lower ascending or spread- 

 ing ; staminate spikelets 3" -6" long, scales acute or 

 awn-pointed, outer 5-nerved, the inner 3-nerved; 

 scales of the linear pistillate spikelets 4"-i2" long, 

 the outer one 5-nerved, with an awn i'-2' long, the 

 inner narrower, 3-nerved, awn-pointed. 



In swamps, New Brunswick to Manitoba, south to 

 Florida and Texas. Canada-rice. Water-rice. June- 

 Oct. 



25. HOMALOCENCHRUS Mieg, in Soc. Phys.-med. Basil, Act. Helv. 4: 



307. 1760. 



[Leersia Soland. ; Sw. Prod. 21. 1788. Not Hedw. 1782.] 

 Marsh grasses with flat narrow generally rough leaf-blades, and paniculate inflorescence. 

 Spikelets I-flowered, perfect, strongly flattened laterally, and usually more or less imbri- 

 cated. Scales 2, chartaceous, the outer one broad and strongly conduplicate, the inner much 

 narrower. Stamens 1-6. Styles short, distinct. Stigmas plumose. Grain ovoid, free. [Greek, 

 in reference to the supposed resemblance of these grasses to Millet.] 



About 5 species, natives of temperate and tropical countries. Besides the following, 2 otherf 

 occur in the southern United States. Type species : Phalaris oryzoides L. 

 Spikelets oblong, their width less than one-half their length, somewhat imbricated. 



Spikelets i'A^-i'A" long; panicle-branches usually rigid. 1. H. virginicus. 



Spikelets 2"-2y 2 " long; panicle-branches generally lax. 2. H. oryzoides. 



Spikelets oval, their width more than one-half their length, jnuch imbricated. 3. H. lenticularis. 



i. Homalocenchrus virginicus (Willd.) Britton. 

 White Grass. Fig. 400. 



Leersia virginica Willd. Sp. PI. 1 : 32s. I7Q7. 

 Asprella virginica R. & S. Syst. 2: 266. 1817. 

 Homalocenchrus virginicus Britton, Trans. N. Y. Acad. 

 Sci. g : 14. 1889. 



Culms glabrous, decumbent, i°-3° long, much 

 branched, slender, smooth. Sheaths usually shorter 

 than the internodes ; ligule short ; blades 2'-6' long, 

 i"-8" wide, acute, usually narrowed toward the base, 

 scabrous ; terminal panicle finally long-exserted, 3'-8' 

 long, its branches generally spreading, usually naked 

 below the middle; lateral panicles smaller and usually 

 included; spikelets \\"-\V long, about \" wide, oblong, 

 appressed; outer scale hispid on the keel and margins; 

 inner scale hispid on the keel; stamens 1 or 2. 



Swamps or wet woods, Maine to Ontario, Florida and 

 Texas. White or False rice. White grama. Aug.-Sept, 



