(GRASS FAMILY.) 559 



I 



nerved, the nerves parallel and separate. Stamens 3 or 2. Stigmas plumose, 

 mostly compound. Ovary smooth. Grain oblong, free. Perennial, smooth 

 marsh-grasses, mostly with creeping bases or rootstocks ; the spikelets in a race- 

 mose panicle. (Name from yXv^epos-, sweet, in allusion to the taste of the grain.) 



$ ! GLYCERIA PROPER. Lower palea conspicuously nerved: styles present: 

 plumes of the stigma branched or toothed: grain grooved on the inner side: leaves 

 flat, the sheaths nearly entire. 



* Spikelets in a crowded panicle, ovate, turgid, more or less compressed; the flowers 

 crowded : lower palea ovate, entire, not very strongly nerved, of a flrm texture, in 

 No. I. becoming ventricose after flowering (almost as in Briza) : upper palea very 

 obtuse and entire : stamens 2. 



1. O. Canadeiisis, Trin. (RATTLESNAKE-GRASS.) Panicle oblong- 

 pyramidal, at length spreading, and the tumid 6 - 8-flowered spikelets drooping ; 

 lower palea acutish, longer than the notched upper one ; leaves long, roughish. 

 (Briza Canadensis, Michx. Poa Canadensis, Beauv.) Boggy places, New 

 England to Penn., Wisconsin, and common northward. July. A handsome, 

 stout grass, 2 3 high. Spikelets 2" long, becoming very broad: glumes purplish. 



2. Cc. ol>tiisa, Trin. Panicle narrowly oblong, dense; the 6 -7-flowered 

 spikelets erect, sJiort-pedicelled ; lower palea obtuse, the upper as long when old. 

 (Poa obtusa, Muhl.) Bogs, E. New England to Penn., near the coast ; rare. 

 Aug. Culm stout, l-2 high, very leafy: leaves long, smooth. Spikelets 

 3" long, pale. 



3. O. elongata, Trin. Panicle narrowly racemose, elongated (1 long), 

 recurving; the branches appressed, bearing the 3-4-flowered erect short-pedi- 

 celled spikelets nearly to the base ; lower palea obtuse, rather longer than the 

 upper; leaves very long (1 or more), rough. (Poa elongata, Torr.) Wet 

 woods, New England to Michigan, and northward. July. Spikelets pale, 1"- 

 l long. 



* * Spikelets oblong, diffusely panicled, nearly terete : lower palea oblong or oval, trun- 



cate-obtuse, prominently 1 -nerved; the upper one ^-toothed: stamens 3 or 2. 



4. O. nei'Vata, Trin. Branches of the broad and open panicle capillary, 

 fit length drooping, the very numerous small spikelets ovate-oblong, 3 - 7-flowered ; 

 leaves rather long. (Poa nervata, Willd. P. striata, Michx. P. parviflora, 

 Pursh.) Moist meadows; very common. June. Culm erect, l-3 high. 

 Spikelets seldom 2" long, commonly purplish. 



5. O |saSIill, Trin. Branches of the rather simple panicle capillary, erect- 

 spreading, rough ; the spikelets usually few, somewhat appressed, oblong-linear, 5-9- 

 flowered (pale, ^ long) ; lower palea oblong, minutely 6-toothed, the upper lancer 

 late, conspicuously 2-toothed; leaves short, sharp-pointed, pale. (Windsoria 

 pallida & Poa dentata, Torr.) Shallow water ; common, especially northward. 

 j u i v . Culms slender, l-3 long, ascending fiom a creeping Inse. 



6. O. aqiultica, Smith. (REED MEADOW-GRASS.) Panicle much 

 branched, ample (8' - 15' long) ; the numerous branches ascending, spreading with age; 

 spikelets oblong or linear-oblong, 5-9-flowered (usually purplish. 2'' - 3' long)j 



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