HITCHCOCK AND CHASE—NORTH AMERICAN PANICUM. 221 
agrees with these specimens except that the spikelets are said to be glabrous. But 
this statement is probably an error of observation or of description, since the author 
adds, ‘‘Related to Panicum lanuginosum Ell., and separated from it by having a 
longer, softer pubescence and its leaves not being ciliate.’’ Since the spikelets of 
P. lanuginosum as described by Ashe (P. huachucae silvicola) are pubescent, this dif- 
ference would probably have been noted in the contrast of the two species. A por- 
tion of the specimen mentioned above has been deposited in the National Herbarium 
and has been chosen as the type of P. orangense Ashe. Itis the early autumnal form. 
Panicum ciliosum Nash, Bull. Torrey Club 26: 568. 1899. ‘‘Type collected by 
S. M. Tracy, at Biloxi, Mississippi, September 1, 1898, no. 4580.’’ The type, in 
Nash’s herbarium, is the early autumnal form with a simple culm and primary panicle 
attached, and without the winter rosette. The specimen of Tracy 4580 in the National 
Herbarium has a winter rosette, the blades 4 to 6 cm. long. In the description the 
ligule is said to be “‘about 0.5 mm. long”’ but in the type it measures 3 mm. long. 
DESCRIPTION. 
Vernal form grayish olive green, velvety to the touch; culms tufted, usually in 
large clumps, 40 to 70 cm. long, slender, lax, spreading, densely villous with fine, 
soft hairs arising from small papille; nodes villous, often a glabrous ring below; 
sheaths shorter than the internodes, soft-villous like the culm, or the upper puberulent 
only, ciliate on the margin; ligules 3 to 4 mm. long; blades thickish but not stiff, 
ascending or spreading, somewhat incurved or spoon-shaped, 5 to 10 cm. long, 5 to 10 
“mmm. wide (the uppermost much smaller), acuminate, narrowed toward the rounded 
base, the margins sometimes papillose-ciliate, the upper surface clothed with short, 
soft hairs with long soft hairs intermixed, especially toward the margins and base, the 
lower surface densely velvety-pubescent; panicles exserted, 6 to 12 cm. long, about 
as wide, loosely flowered, the axis pubescent, the slender flexuous branches spreading 
or ascending, the lower often drooping; spikelets 1.8 to 1.9 mm. long, 1 mm. wide, 
obovate-elliptic, subobtuse, pubescent; first glume one-third the length of the spike- 
let, obtuse or obscurely pointed; second glume and 
sterile lemma equal, slightly shorter than the fruit 
at maturity; fruit 1.6 mm. long, 0.9 mm. wide, ellip- 
tic, subacute. 
Autumnal form widely spreading or decumbent, 
freely branching from the middle nodes, the branches 
repeatedly branching and much exceeding the 
internodes, the ultimate branchlets forming flabel- 
late fascicles; leaves and panicles much reduced, 
the flat blades almost always ciliate and exceeding 
the panicles; winter rosette not appearing until late, the blades 4 to 5 cm. long, 
usually ciliate, otherwise minutely velvety or nearly glabrous. 
The plant bears some resemblance in color and pubescence to P. scoparium, but is 
smaller and much more slender. The vernal form also resembles P. huachucae silvicola 
but is larger and more velvety and is gray-green in color rather than bright green. 
It may be that the form described by Nash as P. cilioswm is a distinct species. 
It differs in having blades glabrous on the upper surface or with a few long hairs only, 
but not velvety, and winter rosettes of large blades. The typical form has been found 
only in Tracy’s garden, at Biloxi, in cultivated soil. Other Biloxi specimens lack 
the large rosettes, probably because not growing in cultivated soil. The following 
specimens, because of the lack of velvety pubescence on the upper surface of the 
blades, may be referred to this form: Mississippi: Biloxi, Chase 4331, Hitchcock 
1079, Tracy 1735, 2867, 3620, 3622, 3645, 4580, 4605; Ocean Springs, Tracy 6469. 
Lovistana: Lake Charles, Hitchcock 1152, Chase 4401. 
Fic. 227.—P. lanuginosum. From 
type specimen. 
