MANUAL OF THE GRASSES OF THE UNITED STATES 83 



Glumes narrow, acute, the second longer than the first; florets olive green. 



10. G. NUUIGENA. 



Lemmas with 5 prominent nerves; second glume 3-nerved; sheaths open. 



Panicle narrow, the branches ascending 16. G. erecta. 



Panicle open, lax. 



Culms relatively thick, commonly 1 m. tall; blades mostly 8 to 12 mm. wide. 



Panicle branches numerous, many-flowered 17. G. pauciflora. 



Panicle branches few, distant, few-flowered 18. G. OTISII. 



Culms slender, decumbent, weak. 



Blades 4 to 8 mm. wide; anthers 1 mm. long. 19. G. pallida. 



Blades 1 to 3 mm. wide; anthers 0.2 to 0.5 mm. long 20. G. pernaldii. 



Section 1. Euglyc£ria Griseb. 



Spikelets linear, nearly terete, usually 

 more than 1 cm. long, appressed 

 on short pedicels; panicles narrow, 

 erect, the branches appressed or 

 ascending after anthesis. The 

 species of Euglyceria, with the 

 exception of Glyceria acutiflora, 

 are very closely allied and appear 

 to intergrade. 

 1. Glyceria acutiflora Torr. (Fig. 



87.) Culms compressed, lax, creeping 



Figure 87. — Glyceria acutiflora. Panicle, X 1; floret, 

 X 10. (Knowlton 86G, Mass.) 



and rooting below, 50 to 100 cm. 

 long; blades flat, lax, 10 to 15 cm. 

 long, 3 to mm. wide, scabrous on 

 the upper surface; panicle 15 to 35 

 cm. long, often partly included, the 

 branches rather stiff, bearing 1 or 2 

 spikelets, or the lower 3 or more; 

 spikelets 5- to 12-flowered, 2 to 4 

 cm. long, 1 to 2 mm. wide, the lateral 

 pedicels 1 to 3 mm. long; glumes 

 about 2 and 5 mm. long; lemmas 7- 

 nerved, acute, scabrous, 6 to 8 mm. 

 long, exceeded by the acuminate, 2- 

 toothed paleas. % — Wet soil and 

 shallow water, New Hampshire to 

 Virginia and West Virginia, west to 

 Michigan, Missouri, and Tennessee; 

 also northeastern Asia. 



2. Glyceria borealis (Nash) Batch- 

 elder. Northern mannagrass. (Fig. 

 88.) Culms erect or decumbent at 

 base, slender, 60 to 100 cm. tall, 

 blades flat or folded, usually 2 to 4 

 mm. wide, sometimes wider; panicle 

 mostly 20 to 40 cm. long, the branches 

 as much as 10 cm. long, bearing 

 several appressed spikelets; spikelets 

 mostly 6- to 12-flowered, 1 to 1.5 

 cm. long; glumes about 1.5 and 3 

 mm. long; lemmas rather thin, obtuse, 

 3 to 4 mm. long, strongly 7-nerved, 

 scarious at the tip, glabrous between 

 the hispidulous nerves. % — Wet 

 places and shallow water, Newfound- 

 land to southeastern Alaska, Pennsyl- 

 vania to Illinois, Minnesota, and 

 Washington, and in the mountains 

 to New Mexico, Arizona, and central 

 California. 



3. Glyceria leptostachya Buckl. 

 (Fig. 89.) Culms 1 to 1.5 m. tall, 

 rather stout or succulent; sheaths 

 slightly rough; blades flat, scaberulous 



