218 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



ida shows that there are all gradations between these extremes, and there appears 

 to be no constant character by which to separate the larger form as a species or even 

 as a well-marked variety. 



3. Panicum aquaticum Poir. Encycl. Suppl. 4 : 281. 1816. lZ-*^ '*» ft ^s^lc-^— jC^**— ^f^- 



Panicum elephantipes Nees, Agrost. Bras. 165. 1829. 



San Antonio, Hitchcock in 1906, Habana, Leon 335. 



Poiret's, type labeled "Panicum aquaticum enc. suppl. * * * Porto Ricco. 

 h. Poiret" is in the herbarium of Cosson in Paris. Nees's type at Munich agrees 

 with this. 



4. Panicum cayennense Lam. Tabl. Encycl. 1: 173. 1791. 



Among other tall grasses in low grounds, pinales, Pinar del Rio, September, 

 Wright 3865; Herradura, Tracy 9073; Isle of Pines, Curtiss 267, Palmer & Riley 10S6, 

 Taylor 34. 



The Grisebach specimen is from western Cuba, 1863, no. 891. A specimen of this 

 species in the Gray Herbarium, without number, is from ''Savannas, Vueltabajo, 

 July 28." 



5. Panicum chloroticum Nees, Agrost. Bras. 164. 1829. Tt>^ *>*'*•' »* — xlhd'C^to 



Punta Brava, Baker HC 4054; Santiago de las Vegas, Hitchcock in 1906; Batabano, 



Hitchcock in 1906; Herradura, Hitchcock in 1906, Tracy 9055; Wright 3456 and 3860 

 in National Herbarium in part; Wright 3860 in Sauvalle Herbarium; Wright 181, 

 189 in the Grisebach Herbarium; Wright 3456 in Sauvalle Herbarium; edge of Lagu- 

 nas, Pinar del Rio, September, Wright 3861. 



The first two specimens cited above are like the type at Munich; the others are 

 more or less pubescent, but appear to be otherwise the same. The type of Pani- 

 cum proliferum pilosum Griseb. in the Grisebach Herbarium is labeled "Around 

 lagunas in wet or damp ground, Hanabana, May 16," no. 186. This is the same 

 as Wright 3860 in the Sauvalle Herbarium. Probably P. bartowense Scribn. & Merr.« 

 is a form of P. chloroticum. It differs from the Brazilian specimen only in its hispid 

 sheaths and from some of the hispid Cuban specimensfDnly in its larger size. Nash's 

 567 from Eustis, Florida, is a low spreading form, with culm about 30 cm. long, but 

 the blades and sheaths pubescent like P. bartowense. P. dichotomiflorum Michx.& 

 (P. proliferum of American authors, not Lam.), common throughout the eastern 

 United States, is smooth throughout, and is usually more or less geniculate-spreading 

 at base, and the blades are usually long and gradually acuminate. In Florida this 

 shows a tendency to become pubescent. Combs & Rolfs 94 from Lake City, Florida, 

 has the habit of P. dichotomiflorum, but the blades are pubescent on the upper sur- 

 face. The spikelets of P. dichotomiflorum vary in length from 2 to 3 mm. It would 

 appear that there is one variable species, including P. dichotomiflorum Michx., 

 P. chloroticum Nees, and P. bartowense Scribn. & Merr. The West Indian specimens 

 resemble more closely P. chloroticum in habit, and for the present they are referred, 

 to this species. Other specimens of the same in the National Herbarium are: Baha- 

 mas, Nassau, Curtiss 177; Cat Cay, Brace 3742. Bermuda: Hamilton, Millspaugh 126. 

 Porto Rico: Unado, Britton & Cowell 432. South America: Brazil, Riedel 959, Salz- 

 mann (P. hygrophilum Salzm.); Paraguay, Morong 1002; Uruguay, Arechavaleta. 



Wright's 3456 and 3861 cited above have larger spikelets than the other Cuban 

 specimens (3 mm. long), but this appears to be a variable character. Wright 3456 

 is the type of P. proliferum strictum Griseb. c Wright 3456 in the Gray Herbarium 

 is from "Lagunas, Almacigos, Nov. 23." 



6. Panicum chrysopsidifolium Nash in Small, Fl. Southeast. U. S. 100. 1903. 

 Wright 3453 in part; Wright M54 in -part; Wright 3461 in part; Herradura, Si'icAcocyfc 



in 1906; Consolacion del Sur, Palmer & Riley 481; Isle of Pines, Palmer dc Riley 982. 



«U. S. Dept. Agr. Div. Agrost. Circ. 36 : 3. 1901. cCat. PI. Cub. 232. 1866. 



& Fl. Bor. Amer. 1 : 48. 1803. 



