HITCHCOCK AND CHASE—-NORTH AMERICAN PANICUM. 259 
© 152. Panicum tenue Muhl. 
Panicum tenue Muhl. Descr. Gram. 118.1817. No locality isgiven. ‘‘P. deustum 
Brickell et Enslin,’’? an unpublished name, is cited as synonym. The type, in the 
Muhlenberg Herbarium, consists of three plants with attached label bearing the name 
“Panicum deustum;”’ these are from 10 to 30 cm. high, the panicles immature, the 
sheaths sparsely appressed-pilose, the blades puberulent on the lower surface and 
with conspicuous white margins. 
Panicum deustum Brickell & Enslin; Muhl. Descr. Gram. 119. 1817, not Thunb. 
1794. This herbarium name is given asasynonym of P. tenue, of which it isatyponym. 
Panicum liton Schult. Mant. 2: 250.1824. Based on P. tenue Muhl., Muhlenberg’s 
description, slightly rearranged, being copied, ‘‘ Nomina mutanda, ob tenue Roxb. et 
deustum Thunb. antiquiora.’’ Panicum tenue Roxb. 1813,¢is a nomen nudum, the 
description not being published until 1820.4 
Panicum unciphyllum Trin. Gram. Pan. 242.1826. Trinius states in regard to his 
specimen, ‘‘V.spp. Am. Bor. (TRatTtTINIck).’’ The type, in the Trinius Herbarium, 
is the vernal form, with sparsely appressed-villous culms and sheaths and puberulent 
blades. Asstated under P. columbianum, Trinius’s species was misunderstood because 
the specimen sent from St. Petersburg as a part of the type proved on a subsequent 
examination of Trinius’s herbarium to be not the type but a specimen of P. coluwm- 
‘bianum which was on the same sheet with the type specimen. The label accompany- 
ing the latter reads, ‘‘Panicum unciphyllum m. Pan. heterophyllum Muhl. (teste 
Nees) an Pluckn. Tav. 92 f. 8, ex herb. Enslini, spmna Am. bor. Trattinick.”’ 
_ Panicum macrum Kunth, Réy. Gram. 1:40. 1829. Based on P. tenue Mubl., 
the name presumably changed because of P. tenue Roxb. 
Panicum parvulum Muhl.; Scribn. & Merr. U. 8. Dept. Agr. Div. Agrost. Cire. 
27: 4. 1900, not Trin. 1834. This name, found in Muhlenberg’s herbarium, is given 
as a synonym of P. tenue. 
l DESCRIPTION. 
Vernal form olive green; culms in rather small tufts, 20 to 55 cm. high, slender, 
erect from a more or less geniculate base, glabrous, or the lower internodes sparsely 
appressed-pubescent, the nodes glabrous, appressed-pubescent, or appressed-pilose; 
sheaths usually much shorter than the internodes, puberulent between the nerves 
to sparsely appressed-pilose, or the upper glabrous; ligules 0.3 to 0.5 mm. long, dense; 
blades distant, ascending or speading, 2 to 5 cm. long, 3 to 4 mm. wide, rather thick 
and with a cartilaginous, often white, margin, involute-pointed, usually densely 
puberulent beneath, glabrous on the upper surface or puberulent toward the base; 
panicles long-exserted, 3 to 5 cm. long, about as wide, pyramidal, open, rather few- 
flowered, the flexuous branches spreading; spikelets 1.6 to 1.7 mm. long, elliptic, 
subobtuse, densely puberulent; first, glume one-fifth as long as the spikelet or less, 
obtuse; second glume shorter than the fruit and sterile lemma; fruit 1.4 to 1.5 mm. 
long, elliptic, subobtuse. : 
Autumnal culms erect or leaning, sparingly branching from the middle nodes, the 
branches in small fascicles, shorter than the primary inter- 
nodes, the blades not much reduced; winter rosette con- 
spicuous, the thick, cartilaginous-margined, involute-pointed 
blades 3 to 5 cm. long, 4 to 7 mm. wide, persistent (but usu- 
ally dead) during the succeeding year. 
This species seems to be intermediate between P. albo- 
marginatum and P. ensifolium, differing from the first in 
being pubescent and in having taller, more slender 
culms, sparingly branched. From P. ensifoliwm it may be distinguished by the larger, 
Fig. 281.—P. tenue. From 
type specimen. 
a Cat. Fl. Ind, 1813. b Roxb. FI, Ind, 1: 313. 1820, 
