620 MISC. PUBLICATION 200, U. S. DEFT. OF AGRICULTURE 



11. Panicum ciliatum Ell. (Fig. 1286.) Vernal culms 5 to 30 cm 

 tall; sheaths ciliate on the margin; blades 3 to 6 cm long, 3 to 8 mm 

 wide, the uppermost often much smaller, ciliate with stiff hairs 2 to 

 3 mm long; panicle 3 to 4 cm long, the axis pilose, branches spreading; 

 spikelets 1.8 to 2 mm long, pilose. Autumnal mats with slightly 



smaller blades. % - — Low pine- 

 lands and hammocks, Coastal Plain, 

 North Carolina to Florida and 

 Louisiana; Mexico (fig. 1287). 



12. Panicum polycaulon Nash. 

 (Fig. 1288.) Vernal culms 10 to 20 

 cm tall; blades mostly narrower 

 than in P. ciliatum, panicle similar; 

 spikelets 1.5 to 1.6 mm long (rarely 

 as much as 2 mm), glabrous. Au- 

 tumnal mats very dense. % — 

 Low pine woods, Coastal Plain, 

 Florida, Alabama, and Mississippi; 

 West Indies. 



13. Panicum strigosum Muhl. 

 (Fig. 1289.) Vernal culms 15 to 30 

 cm tall, the culms and sheaths 

 sparsely pilose; nodes bearded; 

 blades mostly 5 to 7 mm wide, pilose 

 on both surfaces, stiffly ciliate; pan- 

 icle 4 to 6 cm long, axis and 

 branches pilose; spikelets 1.3 to 1.5 

 mm long, glabrous. Autumnal 

 phase a dense mat. % — Sandy 

 woods, Virginia and Tennessee to 

 Florida and Louisiana; Mexico and 

 Cuba to Colombia (fig. 1290). 

 3. Angustifolia.— Densely tufted, 



grayish green; ligules less than 



1 mm long; blades narrow, 



usually stiff, with prominent nerves, sometimes longitudinally 



wrinkled, often ciliate at base; spikelets attenuate at base, rather 



strongly 7-nerved, papillose-pubescent; first glume narrow and 



Figure 1282.— Panicum laxiflorum. Panicle, 

 X 1; two views of spikelet, and floret, X 10. 

 (Curtiss 6635, Fla.) 



Figure 12S3.— Distribution of 

 Panicum laxiflorum. 



Figure 1284.— Panicum xalapevse. 

 Two views of spikelet, and floret, 

 X 10. (Type.) 



sheathing at base. Autumnal culms repeatedly branching, 

 forming bushy crowns; blades greatly reduced. 

 14. Panicum aciculare Desv. (Fig. 1291.) Vernal culms ascending 

 from a spreading base, 20 to 50 cm tall, appressed-pubescent below; 



