POACEAE 111 



1. Hydrochloa fluitans ( Michx. ) Nash. Floating or creeping. Stems 1 m. long or 

 less, slender, much branched : leaf-sheaths sparingly pilose at the summit ; blades 1-4 cm. 

 long, 1.5-4 mm. wide : staminate spikelets 4.5-5 mm. long : stamens about 3 mm. long : 

 pistillate spikelets about 2. 5 mm. long. 



In water or on muddy banks, North Carolina to Florida. Summer and fall. 



43. FHARUS L. 



Monoecious, usually tall, grasses, with ample panicles and large oblique long-petiolate 

 feather-veined leaf-blades with numerous veinlets, the petioles twisted, hence reversing the 

 leaf. Spikelets articulated below the scales, of two kinds, in pairs upon the branches of 

 the panicle, one sessile, pistillate, the other much smaller, pedicellate, staminate. Scales 



3 ; in the staminate spikelets membranous, somewhat broadened, the 2 outer empty, the 

 first a little shorter, the second longer than the flowering scale ; the third scale en- 

 closing a flower but no palet ; in the pistillate spikelets the outer two scales membranous, 

 empty, many-nerved, subequal, the third scale much longer than the others, narrow, 

 at length indurated, nearly closed by the involute margins, enfolding a 2-toothed mem- 

 branous palet which is convolute around the flower. Stamens 6. Styles filiform, elongated, 

 united to near the apex. Stigmas papillose. 



1. Pharus latifolia L. A leafy perennial. Stems 6-10 dm. tall : leaf -sheaths longer 

 than the internodes, concealing the stems ; petiole-like base of the blades 1-5 cm. long ; 

 blades oblanceolate to elliptic, acute, commonly 1-2 din. long, 3-4 cm. wide : panicle 1-2 

 dm. long, its branches finally widely spreading : sessile spikelet about 9 mm. long, the 

 empty scales brown, acute, the flowering scale about twice as long as the empty ones, 

 cylindric, about 1.5 mm. in diameter, densely pubescent with spreading glandular-tipped 

 hairs, abruptly acute at the naked apex ; pistillate spikelet 3-5 mm. long, the apex about 

 reaching the summit of the sessile spikelet. 



In hammocks, near Orange Lake, Florida. Summer. 



44. LUZfOLA Juss. 



Creeping monoecious marsh or aquatic grasses, with flat leaf -blades and open terminal o r 

 lateral panicles. Spikelets small, articulated below the scales, 1 -flowered, the staminate 

 and smaller pistillate in separate panicles. Scales 2, awnless ; in the staminate spikelet 

 thin-membranous, the first empty, broader but scarcely shorter than the second which en- 

 closes a flower but no palet ; in the pistillate spikelet membranous, the first scale striately 

 many-nerved, broader than the second which encloses a flower. Stamens 6-18. Styles 

 short, distinct. Stigmas plumose with simple hairs. 

 Staminate and pistillate spikelets borne in panicles on different stems : pistillate 



spikelets less than 3 mm. long. 1. L. Peruviana. 



Staminate and pistillate spikelets borne in separate panicles on the same stem : 



pistillate spikelets about 4 mm. long. 2. L. Alabamen&is. 



1. Luziola Peruviana Pers. Stems finally branching and rooting at the lower 

 nodes, 4 dm. long or less : leaf -blades elongated and narrow : staminate panicles 3-6 cm. 

 long, the branches erect, the spikelets about 6 mm. long : pistillate panicles 4-6 cm. long, 

 the branches spreading or ascending, the spikelets 2-2.5 mm. long. 



In ditches and in wet usually grassy places, 'Louisiana. Summer and fall. 



2. Luziola Alabamensis Chapm. Stems finally branching and rooting at the lower 

 nodes, 1-3 dm. long : leaf -blades elongated and narrow, usually much exceeding the pan- 

 icles : panicles 3-8 cm. long, often included below in the upper leaf -sheath, the branches 

 commonly ascending or erect : staminate spikelets 5-6 mm. long : pistillate spikelets about 



4 mm. long. 



In wet places, Alabama and Mississippi. Summer and fall. 



45. ZIZANIOPSIS Doell & Aschers. 



Tall robust perennial monoecious aquatic grasses, with creeping rootstocks, long flat 

 leaf -blades and ample terminal panicles. Spikelets with a more or less prominent carti- 

 laginous ring at the base, 1-flowered, narrow, articulated below the scales, flattened, of 2 

 kinds, the staminate at the base of, the pistillate terminating, the branches of the narrow 

 panicle. Scales 2, membranous, concave, acute, the first empty, awned in the pistillate 

 spikelets, a little broader than the scarcely shorter awnless second scale which encloses a 

 flower but no palet. Stamens 6. Styles united. Stigmas plumose with short hairs. 



