24 POACEAE. 



one-half to two-thirds as long as the whole 3pikelet; second and third scales 

 7-9-nerved. 



A weed, Crooked Island : Cuba ; Forto Rico ; Guadeloupe ; Antigua ; continental 

 tropical America. 



13. Panicum dichotomifldrum Miehx Fl. Bor. Am. 1: 48. 1803. 



Panicum bartowense Scribn. & Merr. Circ U. S. Dept. Agric. Agrost. 35: 

 3. 1901. 



Culms at first erect, 3-6 dm. tall, simple, later decumbent and geniculate, 

 1-1.5 m. long, branched at all the upper nodes. Sheaths loose, glabrous, or 

 papillose-hispid, somewhat flattened; leaves 1.5-6 dm. long, 4-20 mm. wide,' long- 

 acuminate, scabrous on the margins and oecasionaly on the nerves ; panicles 

 pyramidal, 1-4 dm. long; spikelets 2-3 mm. long, crowded, lanceolate, acute, 

 glabrous, sometimes purplish; first scale about one-fourth as long as the spike- 

 let; second and third scales about equal, acute, 5-7-nerved; fourth scale elliptic, 

 shining. 



Swamps and water holes, Great Bahama, North Bimini, Andros, New Provi- 

 dence, Cat Cay, Watling's Island, Crooked Island, and Great Exuma : Maine to 

 Nebraska, Florida and Texas ; Bermuda ; Cuba. Recorded by Coker as P. ele- 

 phantipes Nees ; has been confused with P. proliferum Lam. Spreading Witch- 

 grass. 



14. Panicum amarulum Hitchc. & Chase. Contr. U. S. Nat. Herb. 15: 96. 1910. 



Culms rather stout, tufted, glabrous, glaucous, 4-15 dm. high, the sheaths 



overlapping. Leaves 1.5-3 dm. long, 6-12 mm. wide, leathery, the margins 



involute; panicle narrow, sometimes 7 dm. long, its branches erect; spikelets 



about 5 mm. long; first scale about one-half as long as the whole spikelet, the 



third somewhat longer than the second. 



Sea-beaches and sand dunes. Great Bahama and New Providence : Virginia to 

 Florida and Mississippi ; Cuba ; Jamaica. Sea-beach Grass. 



15. Panicum trichoides Sw. Prodr. 24. 1788. 



Panicum brevifolium of authors. Not L. 1753. 



Panicum capUla-ceum Lam. Tabl. Encycl. 1: 173. 1791. 



Culms slender, ascending or erect, 6 dm. high or less, pubescent. Sheaths 

 pubescent and ciliate; leaf-blades membranous, 2-7 cm. long, 1-2 cm. wide, 

 ovate-lanceolate, acuminate at the apex, cordate-clasping at the base, glabrous 

 or sparingly pubescent; panicles 2 dm. long or less, their branches filiform, 

 spreading and ascending; spikelets nearly ellipsoid, about 1.2 mm. long, spar- 

 ingly hirsute; first scale acute, 1-nerved, about one-half as long as the whole 

 spikelet; second and third scales 3-nerved. 



Turks Islands : Jamaica : Cuba to Tortola and Trinidad ; tropical continen- 

 tal America. Hair-like Panic-grass. 



16. Panicum coerulescens Hack.; Hitchc. Contr. Nat. Herb. 12: 219. 1909. 



Culms slender, tufted, glabrous, at first erect and simple, later reclining 



and with short, fascicled branches at the nodes, 8 dm. long or less. Sheaths 



glabrous, or the lower sometimes pubescent ; leaves of the vernal stage 5-8 cm. 



long, 3-7 mm. wide, glabrous or very nearly so ; panicles of the vernal stage 



3-7 cm. long, those of the autumnal stage usually reduced to a few spikelets; 



spikelets about 1.5 mm. long, obovoid, glabrous; first scale about one-third 



the length of the whole spikelet. 



Moist places and in swamps, Great Bahama. Andros, New Providence, Cat Island 

 (?) Crooked Island: New Jersey to Florida and Texas; Cuba. Referred by Dolley 

 to P. dichotomum L. Bluish Panic-grass. 



17. Panicum neuranthum Griseb. Cat. PL Cuba 232. 1866. 



Culms tufted, slender, at length much branched, 3-7.5 dm. tall. Sheaths 

 glabrous, or the lower pubescent ; leaves smooth and glabrous, the primary 



