HITCHCOCK AND CHASE — NORTH AMERICAN PANICUM. 329 



In the original description P. decolorans is given as perennial, but the type lacks 

 the basal portion, while its general character shows its relationship to those species 

 of Capillaria having* large spikelets. The pubescence appears to be extremely vari- 

 able even on the same plant. 



DISTRIBUTION. 



Fields and waste ground, plateau of central Mexico. 



Mexico: Queretaro, Hitchcock 5822, Humboldt (Paris Herb.); Cardenas, Hitchcock 

 5712. 



DOUBTFUL SPECIES. 



In the following list are given the names assigned to species of 

 Panicum and credited to North America which have not been 

 accounted for in the preceding pages and which can not definitely be 

 excluded from Panicum as here limited. The list includes several 

 nomina nuda which are mentioned only because the names are given 

 in the Index Kewensis and consequently have become a part of the 

 literature upon the genus. 



Panicum ambitiosum Fourn. Mex. PI. 2: 30. 1886. " Orizaba (Thomas in herb. 

 Buchinger); Vera Cruz (herb. Uzac)." We have not seen the type nor an authentic 

 specimen of this species. From the description it appears to be a species of Ichnan- 

 thus. The name was given by Hemsley as a nomen nudum. 



Panicum arundinariae Trim; Fourn. Mex. PL 2: 25. 1886. Fournier credits this 

 name to "Trin. in sched. coll. Schiedeanae" and cites as the first of several speci- 

 mens, "Absque loco (Schiede)." We have not seen the Schiede specimen, which is 

 the type. Schaffner's no. 279, cited by Fournier, which agrees fairly well with his 

 description, is P. virgultorum. Trinius's name is mentioned earlier as a nomen nudum 

 by Steudel& and Hemsley. a 



Panicum brevifolium Walt. Fl. Carol. 73. 1788. No particular locality is given by 

 Walter but his plants were all collected in the valley of the lower Santee River, South 

 Carolina. The author evidently intended to refer his species to P. brevifolium L., as 

 he quotes the Linnsean diagnosis. We may thus consider that Walter misapplied the 

 name. What species Walter had, which he referred to P. brevifolium, is uncertain. 



Panicum buchingeri Fourn. Mex. PL 2: 30. 1886. "Orizaba (Thomas in herb. 

 Buchinger)." We have not seen the type. From the description it appears to 

 be P. virgatum L. The name is listed earlier by Hemsley without description. 



Panicum cartilagineum Muhl. Descr. Gram. 128. 1817. "Habitat in Georgia." 

 This is not in the Muhlenberg Herbarium. The description suggests P. leucothrix Nash. 



Panicum conchatum Fourn. Mex. PL 2 : 25. 1886. " Sierra de San Cristobal (Schaffn. 

 n. 204, octobri)." This name was earlier listed by Hemsley d without description. 

 Specimens of this number of Shaffner's collection were examined at the herbarium of 

 Drake de Castillo and at the Halle Herbarium, but the notes taken at the time are 

 not full enough to enable us to describe this species, which is not represented in the 

 National Herbarium, nor is Founder's description at all 'adequate. This appears to 

 be a distinct species of the Parviglumia and most nearly related to P. schmitzii Hack., 

 from which it differs in having a longer, more oblong spikelet with a longer first 

 glume. 



Panicum cordifolium Desv. Opusc. 88 [90]. 1831. "Habitat in America boreali." 

 We have not seen the type. The description applies well to P. commutatum Schult. 



Panicum cor dovense Fourn. Mex. PL 2: 26. 1886. " Cordova (Schaffn. n. 293 in 

 herb. Franq.)." The type is in the herbarium of Drake de Castillo. The notes 

 taken upon this specimen do not enable us to identify it with any other Mexican 

 species, hence it is retained among the doubtful species until more material can be 



« Biol. Centr. Amer. Bot. 3: 485. 1885. cBiol. Centr. Amer. Bot. 3: 486. 1885. 



b Norn. Bot. ed. 2. 2: 253. 1841. ^Op. eit. 487. 



