MANUAL OF THE GRASSES OF THE UNITED STATES 



559 



vations compressed-keeled; blades not more than 6 mm wide, softly 

 pilose; racemes 4 to 8, ascending, pale, 8 to 12 cm long, the triangular 

 rachis narrowly margined; spikelets about 3 mm long; first glume 

 hyaline, obsolete or nearly so; second glume and sterile lemma finely 

 7- to 9-nerved, glabrous or very obscurely pubescent, barely exceeding 



the pale, slightly apiculate 

 fertile lemma, o — Sandy 

 fields, Florida, rare; Isla de 

 Pinos, Cuba. 



8. Digitaria filiformis (L.) 

 Koel. (Fig. 1168, A.) 

 Culms in small tufts, slender, 

 usually erect, 10 to 60 cm 

 tall, rarely taller, those of 

 a tuft very unequal; lower 

 sheaths pilose, the upper 

 mostly glabrous ; blades 



Figure 1167.— Digitaria simpsoni. Plant, X 1; spikelet 

 and floret, X 10. (Curtiss 6422, Fla.) 



Figure 1168.— A, Digitaria 

 filiformis. Plant, X 1; spike- 

 let and floret. X 10. (Bis- 

 sell, Conn.) B, D. laevi- 

 glumis. Spikelet, X 10. 

 (Type coll.) 



erect, usually 5 to 15 cm long (longer in robust plants), 1 to 4 

 mm wide; racemes mostly 1 to 5, unequal, erect or ascending, mostly 

 less than 10 cm long, somewhat distant, not fascicled; spikelets 1.5 

 to 1.7 mm long; first glume wanting; second glume and sterile lemma 

 pubescent with short capitellate hairs, sometimes nearly glabrous, the 

 glume shorter than the spikelet; fertile lemma dark brown, slightly 

 apiculate. o — Sandy fields and sterile open ground, Xew Hamp- 

 shire to Iowa and Kansas, south to Florida, Texas, and Mexico 



65974°-35 36 



