THE NORTH AMERICAN SPECIES OF PENNISETUM. 221 



Pennisetum purpurascens H. B. K. Nov. Gen. & Sp. 1: 113. 1816. "Mexicani, 

 VolcandeJorullo. " The type has not been examined, but the description applies 

 well to the robust plants of Mexico. The blades are described as scabrous on the 

 upper surface and on the margin and glabrous beneath, and the sterile floret as having 

 a palea. 



Pennisetum uniflorum H. B. K. Nov. Gen. & Sp. 1: 114. pi. 34- 1816. "Prov. 

 Novae Andalusiae, juxta Cumanacoa, " [Venezuela]. The description and plate 

 identify the species. The sheaths are described as pubescent, the blades scabrous 

 on the upper surface and margin, and glabrous beneath; the sterile lemma empty. 



Panicum densispica Poir. in Lam. Encycl. Suppl. 4: 273. 1816. Based on "Pani- 

 cum cenchroides Rich, non Lam. " 



Panicum triticoides Poir. in Lam. Encycl. Suppl. 4: 274. 1816. Described from a 

 specimen in Desfontaines's herbarium, its source unknown. The type has not been 

 examined. The description applies well to Pennisetum setosum, to which Doell 20 

 refers it. The sheaths are described as glabrous but pilose at the mouth, the blades 

 as rough and sparsely pilose on both surfaces. 



Setaria cenchroides Roem. & Schult. Syst. Veg. 2: 495. 1817. Based on Panicum 

 cenchroides L. Rich. 



Pennisetum triticoides Roem. & Schult. Syst. Veg. 2: 877. 1817. Based on Panicum 

 triticoides Poir. 



Gymnothrix geniculata Schult. Mant. 2: 284. 1824. "Setaria geniculata Sieb. Fl. 

 Martin. * * In Martini ca. " The detailed description identifies the species. 

 The sheaths are described as glabrous and the blades as scabrous on both surfaces. 



Pennisetum alopecuroides Desv.; Hamilt. Prodr. PL Ind. Occ. 11. 1825. "India 

 occidentali. " The type has not been examined. The description of the "involucre " 

 as pilose identifies the species. The sheaths are described as glabrous and the blades 

 as subscabrous. 



f Pennisetum erubescens Desv.; Hamilt. Prodr. PI. Ind. Occ. 11. 1825. "St. 

 Thomas. " The brief diagnosis is insufficient for identification, but the species is 

 probably P. setosum. The leaves are not described. 



Pennisetum richardi Kunth, Rev. Gram. 1: 49. 1829. Based on Panicum cenchroides 

 L. Rich. 



Pennisetum sieberi Kunth, Rev. Gram. 1: 50. 1829. Based on "Gymnothrix 

 geniculata Schult. — Setaria geniculata Sieb, herb. Mart." 



Pennisetum hirsutum Nees, Agrost. Bras. 284. 1829. "In ripa flurninis S. Fran- 

 cisci ad Joazeiro provinciae Bahiensis et Pernambucensis; nee non in * * * pro- 

 vinciae Piauhiensis." The specimen collected by Martius in Bahia, which was 

 examined by A. S. Hitchcock in the Munich Herbarium, is probably the type. The 

 sheaths are described as tuberculate-pilose toward the summit and the lower blades as 

 tuberculate-pilose on both surfaces, the upper blades as sparsely pilose. 



Pennisetum pallidum Nees, Agrost. Bras. 285. 1829. "Habitat. * * * ad 

 latera montium de Mentanha et Itambe, districtus adamantini, provinciae Minarum." 

 The type specimen, collected by Martius, was examined by A. S. Hitchcock in the 

 Munich Herbarium. The sheaths and blades are described as tuberculate-hirsute. 



Pennisetum fiavescens Presl, Rel. Haenk. 1: 316. 1830. "Hab. in Mexico." The 

 type specimen was examined by A. S. Hitchcock in the herbarium of the German 

 University at Prag. The sheaths are described as smooth, the blades as nearly glabrous 

 beneath and tuberculate- villous above. 



Pennisetum dasistachyum Desv. Opusc. 76. 1831. "Habitat in Guyana. ' ' The type 

 has not been examined. The description of the bristles identifies the species. Des- 

 vaux cites "Panicum cenchroides Rich, nee Lamk., densi-spica Poir." as synonyms. 

 The sheaths and blades are described as glabrous, the sheaths bearded at the mouth. 



28 In Mart. Fl. Bras. 2<: 306. 1877. 



