38 POACEAE. 



Panicularia pauciflora (Presl.) Kuntze. Stems SO-100 cm. high, smooth; 

 leaf blades 10-20 cm. long, nearly 1 cm. broad, acute, scabrous; sheaths nearly 

 equalling the internodes; panicle loose, 15-20 cm. long, usually purplish, its 

 base included in the upper sheath; branches slender, spreading, 2-5 at a node, 

 flower-bearing above the middle; spikelets 4-5 mm. long, 4-6-flowered ; 

 lemmas prominently 5-nerved, rarely 7-nerved. In moist places or even in 

 water, not rare. 



Panicularia nervata (Willd.) Kuntze. Stems 50-100 cm. tall, slender, gla- 

 brous; leaf blades 15-30 cm. long, ■t-5 mm. wide, scabrous above; panicle 

 6-20 cm. long, long-peduncled, its branches in twos and threes, slender and 

 spreading; spikelets 2-4 mm. long, 4-7-flowered; lemma prominently 7-nerved. 

 In wet places, infrequent. 



Panicularia nervata elata (Nash) Piper. Leaf blades 5-8 mm. broad; stems 

 taller and panicles larger. In wet places in woods. 



Panicularia americana (Torr.) MacM. Reed Meadow Grass. Stems stout, 

 100-150 cm. high; leaf blades 6-15 mm. wide; panicle large and loose, 20-40 

 cm. long, nodding at the top; spikelets 4-7-fio wered ; second glume 2-2.5 mm. 

 long. In wet places, Steptoe, G. R. Vasey; Waitsburg, Horner. 



59. SPARTINA. 



Coarse perennial grasses with strong creeping rootstocks, rigid 

 simple stems and long tough leaves; inflorescence of one-sided 

 spreading or erect alternate spikes; spikelets 1-flowered, narrow, 

 deciduous, borne in two rows on the rachis, articulated with the 

 very short pedicels below the glumes; glumes keeled, very un- 

 equal ; lemma keeled, equalling or shorter than the second glume; 

 palea often longer than its lemma; grain free. 



Plant stout; spikelets 12-14 mm. long. 5. michauxiana. 



Plant slender; spikelets 6-9 mm. long. S, gracilis. 



Spartina michauxiana Hitchc. Stems 1-2 m. tall, simple, smooth; leaf 

 blades flat, keeled, long-acuminate, involute in age, scabrous on the margins; 

 spikes 5-20, 5-12 cm. long, ascending, sometimes peduncled; spikelets closely 

 imbricated; glumes very scabrous on the keels, awn-pointed; lemma scabrous 

 on the midrib, which terminates below the 2-toothed apex. Rocky banks of 

 Snake River at Almota and Lake Tesemini, Idaho. 



Spartina gracilis Trin. Stems 30-60 cm. high, erect, stiff; leaf blades pale 

 green, flat or slightly involute, 15-30 cm. long, 2-4 mm. wide, somewhat 

 scabrous; spikes mostly 5-7, appressed, 1.5-2 cm. long; glumes acute, scabrous 

 on the keels; lemma entire, acute, scabrous on the keels. In alkaline soil, 

 Spokane County. 



60. BECKMANNIA. 



Tall erect perennials ; inflorescence a terminal panicle of erect 

 spikes; spikelets 1-2-flowered, globose, compressed; glumes mem- 

 branous, saccate, obtuse or abruptly acute; lemmas 1 or 2, 

 narrow, thin-membranous; palea hyaline; grain oblong, free, 

 enclosed in the lemma. 



Beckmannla erucaefonnis (L.) Host. Perennial, the stems stout, 60- 

 90 cm. tall, glabrous throughout; leaf blades 10-30 cm. long, 6-10 mm. wide. 



