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



157. Panicum urvilleanum Kunth. (Fig. 1539.) Culms solitary 

 or few in a tuft, 50 to 100 cm tall, erect from a creeping rhizome; 

 nodes densely bearded; sheaths overlapping, densely retrorse-villous; 

 blades elongate, 4 to 7 mm wide, tapering from a flat base to a long 

 involute setaceous point, strigose or glabrous; panicle 25 to 30 cm 

 long, the slender branches ascending; spikelets 6 to 7 mm Ion 

 densely silvery- or tawny- villous ; first glume clasping, from two-thir 



FIGURE 1533. Distribution of 

 Panicum rhizomatum. 



FIGURE 1534. Pani- 

 cum hians. Spikelet 

 and floret, X 10. 

 (Type.) 



FIGURE 1535 Distribution of 

 Panicum hians. 



to nearly as long as the spikelet. 91 Sandy deserts, Arizona and 



southern California; Argentina, Chile. 



14. Obtusa. StoJoniferous wiry perennial; ligules about 1 mm long; 



panicles narrow, the few appressed branches densely flowered; 



spikelets short-pediceled, secund, glabrous; fruit smooth and 



shining. 



158. Panicum obtusum H. B. K. VINE-MESQUITE. (Fig. 1540.) 

 Tufted from a knotted crown, the stolons sometimes 2 m long or 

 more, with long internodes and geniculate, swollen, conspicuously 

 villous nodes; culms compressed, 20 to 80 cm tall; blades mostly 

 elongate, 2 to 7 mm wide, glabrous or nearly so; panicles 3 to 12 cm 



FIGURE 1536. Panicum verrucosum. 

 Two views of spikelet, and floret, 

 X 10. (Type.) 



FIGURE 1537. Distribution of 

 Panicum verrucosum. 



long, about 1 cm wide; spikelets 3 to 3.8 mm long, obovoid, brownish, 

 obtuse; first glume nearly as long as the spikelet. 91 Sandy or 

 gravelly soil, mostly along banks of rivers, arroyos, and irrigation 

 ditches, western Missouri to Colorado, south to Texas and Arizona; 

 Mexico (fig. 1541). 

 15. Hemitoma. Aquatic or subaquatic perennial; panicles elongate, 



very narrow; spikeleis subsessile, 3- to 5-nerved, glabrous. 

 159. Panicum hemitomon Schult. MAIDENCANE. (Fig. 1542.) 

 With extensively creeping rhizomes, often producing numerous sterile 

 shoots with overlapping sometimes densely hirsute sheaths; culms 50 

 to 150 cm tall, usually hard; sheaths of fertile culms usually glabrous; 

 blades 10 to 25 cm long, 7 to 15 mm wide, usually scabrous on the 

 upper surface and smooth beneath; panicle 15 to 30 cm long, the 



