HITCHCOCK AND CHASE — GRASSES OF THE WEST INDIES. 327 



Culms firm, erect or decumbent at base only ; 

 blades 3 to 8 cm. long ; Trinidad. 



44. P. cyanescens. 

 Panicles 10 to 20 cm. long, very diffuse; plants 

 tall, not glaucous, decumbent at base. 

 Spikelets viscid, 3 mm. long. 



47. P. glutinosum. 

 Spikelets not viscid, 2 to 2.3 mm. long. 



46. P. millegrana. 

 First glume pointed, usually less than two-thirds 

 as long as the pointed spikelets. 

 Spikelets not over 1.4 mm. long, pubescent; 

 panicle large, diffuse ; culms straggling. 



42. P. trichanthum. 

 Spikelets 2 to 3.5 mm. long. 



Spikelets sparsely hispid ; culms stout, woody. 



48. P. rudgei. 

 Spikelets glabrous. (Diffusa.) 

 Culms as much as 1 cm. thick ; blades 2 cm. 



or more wide 19. P. hirsutum. 



Culms slender ; blades not over 1 cm. wide. 

 Blades 1 to 3 mm. wide ; spikelets 2 to 2.5 

 mm. long; culms glabrous*; sheaths 

 glabrous or nearly so ; plants spread- 

 ing or ascending 17. P. diffusum. 



Blades mostly about 1 cm. wide ; spikelets 

 3 mm. long; culms and sheaths hir- 

 sute ; plants mostly erect. 



18. P. ghiesbreghtii. 



Subgenus PAUROCHAETIUM Hitchc. & Chase. 



1. Panicum distantiflorum A. Rich, in Sagra, Hist. Cuba 11: 304. 1850. 

 Limestone hills at low altitudes, Bahamas to Cuba and Haiti, and in Curagao. 



Originally described from Cuba. 



2. Panicum utowanaeum Scribn. in Millsp. Field Mus. Bot. 2: 25. 1900. 

 Open rocky soil, mostly near the coast, Cuba, Porto Rico, Guadeloupe, and 



Venezuela. Originally described from Porto Rico. 



3. Panicum chapmani Vasey, Bull. Torrey Club 11: 61. 1884. 



Coral sand and shell mounds, southern Florida and the Bahamas. Originally 

 described from Florida. 



TRUE PANICUM. 



4. Panicum geminatum Forsk. Fl. Aegypt. Arab. 18. 1775. 



Moist ground, ditches, and swamps, mostly near the coast, tropical regions of 

 both hemispheres, in America extending north into southern Florida and 

 Texas ; throughout the West Indies. Originally described from Rosetta, Egypt. 



5- Panicum barbinode Trin. Meni. Acad. St. Petersb. VI. Sci. Nat. 1 : 256. 1834. 



Para grass. 



Cultivated and waste ground, especially in moist places, tropical America, 



extending into southern Florida and Texas ; introduced in the warmer parts 



of the Old World. Originally described from Bahia, Brazil. A valuable forage 



