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: Querétaro, 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 narfles are given 
in the Index Kewensis and consequently have become a part of the 
literature upon the genus. 
Panicum ambitiosum Fourn. Mex. Pl. 2: 30. 1886. ‘‘Orizaba (THomas in herb. 
Bucuincer); Vera Cruz (herb. Uzac).’’ We have not seen the type nor an authentic 
specimen of this species. [rom the description it appears to be a species of Ichnan- 
thus. The name was given by Hemsley as a nomen nudum.4 
Panicum arundinariae Trin.; 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. 
Panicum brevifolium Walt. F1. 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 Linnzean 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. 
Bucuincer).’’ 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 isnot inthe Muhlenberg Herbarium. The description suggests /’. leucothriz Nash. 
Panicum conchatum Fourn. Mex. Pl. 2: 25. 1886. ‘‘Sierra de San Cristobal(ScHaFFn. 
n. 204, octobri).’” This name was earlier listed by Hemsley @ 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 Fournier’s description at all adequate. This appears to 
be a distinct species of the Parviglumia and most nearly related to P. schmitzit 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 cordovense Fourn. Mex. Pl. 2: 26. 1886. ‘Cordova (Scuarrn. 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 
a Biol. Centr. Amer. Bot. 3: 485. 1885. ¢ Biol. Centr. Amer. Bot. 3: 486. 1885. | 
b Nom. Bot. ed. 2. 2: 253. 1841. @QOn. cit. 487. 
