GRAMINEAE. 9 1 



20. ZIZANIOPSIS. Doell and Aschers. 



Tall aquatic monoecious grasses, with long flat leaves and paniculate inflor- 

 escence. Spikelets I -flowered, the pistillate borne at the top of the branches, the 

 staminate at the base. Scales 2, nearly equal, membranous, the outer one in the 

 pistillate spikelets broad, acute, and bearing an awn. Stamens 6. Styles united. 

 Grain nearly globose, the pericarp readily separable. [Name in allusion to the 

 resemblance of this grass to Zizania. ] A monotypic genus, of temperate and trop- 

 ical America. 



I. Zizaniopsis miliacea (Michx.) Doell. and Aschers. Zizaniopsis. (I. F. 

 f. 285.) Culms 1-4.5 mm - tall, from a long rootstock. Sheaths loose, glabrous; 

 ligule 8-14 mm. long, thin-membranous; leaves 3 dm. long or more, 1.25-2.5 cm. 

 wide; panicle 3-4.5 dm. long, narrow; branches erect; staminate spikelets 6-8 

 mm. long, the outer scale 5-nerved, the inner 3-nerved; pistillate spikelets about 

 6 mm. long, the outer scale bearing an awn 2-6 mm. long, 5-nerved; inner scale 

 3-nerved. Swamps, Ga. to Ohio (according to Riddell), south to Fla. and Tex. 

 June-July. {Zizania miliacea Michx.) 



21. ZIZANIA L. 



A tall, aquatic monoecious grass, with long flat leaves and an ample panicle. 

 Spikelets 1 -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 N. Am. and Asia. 



I. Zizania aquatica L. Wild Rice. Indian Rice. Water Oats. Reed. 

 (I. F. f. 286.) Culms erect from an annual root, 9-30 dm. tall. Sheaths loose, 

 glabrous; ligule about 6 mm. long, thin -membranous ; leaves 3 dm. or more long; 

 panicle 3-6 dm. long, the upper branches erect, the lower widely spreading; 

 staminate spikelets 6-12 mm. long, outer 5-nerved, the inner 3-nerved; scales of 

 the pistillate spikelets 8-24 mm. long, the outer one 5-nerved, with an awn 2.5-5 

 cm. long, the inner narrower, 3-nerved, awn-pointed; grain 1-3 cm. long. In 

 swamps, N. B. to Manitoba, south to Fla. and Tex. June-Oct. 



22. HOMALOCENCHRUS Mieg. [LEERSIA Sw.] 



Marsh grasses with flat narrow, generally rough leaves and paniculate inflores- 

 cence. Spikelets 1 -flowered, perfect, strongly flattened laterally, and usually 

 more or less imbricated. Scales 2, chartaceous, the outer one broad and strongly 

 conduplicate, the inner much narrower. Stamens 1-6. Styies short, distinct. 

 Stigmas plumose. Grain ovoid, free. [Greek, in reference to the supposed re- 

 semblance of these grasses to Millet.] About 5 species, natives of temperate and 

 tropical countries. Besides the following, 2 others occur in the southern U. S. 



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



Spikelets 2.5-3 mm? long; panicle-branches usually rigid. 1. H. Virginicus. 



Spikelets 4-5 mm. long ; panicle-branches generally lax. 2. H. oryzoides. 



Spikelets oval, their width more than one-half their length, much imbricated. 



3. H. lenticularrs. 



1. Homalocenchrus Virginicus (Willd.) Britton. White Grass. (I. F. f. 

 287.) Culms 3-9 dm, long, much branched, slender. Leaves 5— 15 cm. long, 

 2-16 mm. wide, scabrous; terminal panicle finally open and long-exserted, 7.5-^0 

 cm. long; lateral panicles smaller and usually included ; spikelets 2.5-3 mm. long, 

 about 1 mm. wide; outer scale hispid on the keel and margins; stamens I or 2. 

 Swamps or wet woods, Me. to Ont. and Minn., south to Fla. and Tex. Aug. -Sept. 



2. Homalocenchrus oryzoides (L.) Poll. Rice Cut-grass. (I. F. f. 288 ) 

 Culms 3-12 dm. long, much branched, rather stout. Leaves 7.5-25 cm. long, 

 4-10 mm. wide ; terminal panicle 1.25-2.25 dm. long, finally long-exserted, its 

 branches lax, and later widely spreading ; lateral panicles generally included; 

 spikelets 4-5 mm. long, about 1.5 mm. wide, elliptic; scales pubescent, the outer 

 one hispid on the keel and on the margins; stamens 3. In swamps and along 

 streams, often forming dense tangled masses, N. S. to western Ont., south to Fla 

 and Tex. Also in the temperate parts of Europe and Asia. Aug.-Sept 



