MANUAL OF THE GRASSES OF THE UNITED STATES 



579 



Spikelets depressed plano-convex; culms rather slender. 



Spikelets glabrous 7. P. LIVIDUM. 



Spikelets pubescent 8. P. H ART WEGI ANUM. 



Culms erect to spreading, not rooting at the nodes. 



Spikelets about 1.3 mm long, obovate, glandular-pubescent. 



25. P. BLODGETTII. 



Spikelets 1.5 mm or more long, elliptic or elliptic-obovate, 



the obscure pubescence not glandular. 

 Nodes or some of them appressed-pilose; spikelets green or 



purplish 26. P. CAESPITOSUM. 



Nodes glabrous; spikelets pale or brownish. 



27. P. LAXUM. 



1. Dissecta. Blades flat; rachis foliaceous. Aquatics, subaquatics, 



or plants of wet ground. 



1. Pa spa! um dissectum L. (Fig. 1201.) 

 Glabrous, olive-green, creeping, freely branch- 

 ing, the flowering branches ascending, 20 to 60 

 cm long; blades thin, 3 to 6 cm long, 4 to 5 mm 

 wide; panicles terminal and axillary, the ra- 

 cemes 2 to 4, usually erect, 2 to 3 cm long; 

 rachis 2 to 3 mm wide; spikelets solitary, ob- 

 ovate, subacute, 2 mm long. 91 On muddy 

 and sandy banks of ponds and ditches or in 

 shallow water, New Jersey and Missouri to 

 Florida and Texas; Cuba (fig. 1202). 



2. Paspalum acuminatum Raddi. (Fig. 

 1203.) Culms decumbent at base, sometimes 

 extensively creeping, 30 to 100 cm long; blades 

 4 to 12 cm long, 5 to 12 mm wide; racemes 3 to 

 5, erect or ascending, 3.5 to 7 cm long; rachis 3 

 to 3.5 mm wide; spikelets solitary, 3.5 mm 

 long, abruptly pointed. 91 In shallow 

 water or wet open ground from southern 

 Louisiana and Texas to Argentina. 



3. Paspalum repens Bergius. (Fig. 1204.) 

 Culms mostly submerged, sometimes as much 

 as 2 m long, the sheaths on the floating 



branches inflated; blades usually 10 to 20 cm 

 long, 12 to 15 mm wide; panicle 10 to 15 cm 

 long, of numerous ascending, spreading, or 

 recurved racemes, 3 to 5 cm long, falling entire, 

 the rachis about 1 .5 mm wide ; spikelets solitary, 

 elliptic, 1.4 to 2 mm long, usually pubescent, the 

 sterile lemma pinkish at base. 91 (P. mucrona- 

 tum Muhl.) Floating in sluggish streams or 

 standing water or creeping in wet places, South 

 Carolina to Indiana, Kansas, and Texas, south to Argentina (fig. 1205) 



PASPALUM RACEMOSUM Lam. Branching annual; blades 5 to 12 cm long, 

 1 to 2 cm wide; panicles tawny to purple; racemes numerous, 1 to 2 cm long; spike- 

 lets about 2.7 mm long, pointed; sterile lemma transversely fluted either side of 

 the midnerve. O Sometimes cultivated for ornament. Peru. 



2. Disticha. Creeping with wiry compressed culms and stolons or 



rhizomes; racemes mostly 2, paired or approximate. 



FIGURE 1201. Paspalum dis- 

 sectum. Panicle, X 1; two 

 views of spikelet, and floret, 

 X 10. (Commons 85 Del.) 



FIGURE 1202. Distribution of 

 Paspalum dissectum. 



