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MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



cicled, sparsely long-pilose in the 

 axils; spikelets gray to nearly black, 

 linear, scarcely compressed, 3- to 9- 

 flowered, 3 to 5 mm. long, about 1 

 mm. wide, the pedicels spreading, 

 mostly longer than the spikelets; 

 glumes acute, the first a little less 

 than, the second a little more than, 

 1 mm. long; lemmas loosely imbricate, 

 the rachilla more or less exposed, 

 rounded on the back, acute, 1.2 to 

 1.5 mm. long, 0.5 mm. wide from 

 keel to margin, the nerves obscure; 

 grain 0.6 mm. long. O — Moist 

 open ground and waste places, Maine 

 to Colorado, south to Florida and 

 Texas, south through Mexico and 

 the West Indies to Argentina; Cali- 

 fornia; introduced from Europe. 



Figure 201. — Eragrostis pilosa. Panicle, X 1; floret, 

 and palea, X 10. (Ruth 514, Tex.) 



17. Eragrostis perplexa L. H. Har- 

 vey. (Fig. 202.) Annual resembling 

 E. pilosa, but mostly less slender; 20 

 to 50 cm. tall, or in dry ground 12 to 

 15 cm. tall; blades mostly 3 to 4 mm. 

 wide; panicle less delicate than in E. 

 pilosa and without hairs in the axils; 

 culms below the nodes, keels of the 

 sheaths, and panicle branches bearing 

 small glandular depressions, these 

 often obscure in immature plants. 

 O — Low alkaline areas and buffalo 

 wallows, North Dakota to Kansas; 

 Texas; Colorado. 



Eragrostis virescens Presl. Annual; 

 culms slender, 50 to 60 cm. tall; 

 blades 3 to 6 mm. wide; panicle open, 

 about one third the entire height of 

 the culm, the lower branches mostly 

 solitary, the axils glabrous or nearly 

 so; branchlets and spikelets some- 

 what appressed along the primary 

 branches; spikelets linear, mostly 7- 

 to 9-flowered, 4 to 5 mm. long, pale or 

 greenish, about 1 mm. wide; lower 

 lemmas scarcely 1.5 mm. long. O 

 Adventive, Maryland; ballast, Apala- 

 chicola, Fla.; Chile. Resembling E. 

 diffusa; spikelets smaller. 



Figure 202. — Eragrostis perplexa. Sheath, X 2; 

 panicle, X 1. (Type.) 



18. Eragrostis pectinacea (Michx.) 

 Nees. (Fig. 203.) Resembling E. 

 pilosa; panicles less delicate, the axils 

 glabrous or obscurely pilose, the 

 somewhat larger spikelets appressed 

 along the branches and branchlets, 

 often longer than the pedicels; spike- 

 lets at maturity mostly linear, 5 to 8 

 mm. long; lemmas 1.5 to 1.6 mm. 

 long, the rachilla not or scarcely ex- 



