HITCHCOCK AND CHASE—-NORTH AMERICAN PANICUM. 271 
162. Panicum breve gp. nov. 
DESCRIPTION. 
Vernal form purplish, culms in dense tufts, 5 to 17 cm. high, erect, stiff and wiry, 
glabrous or appressed-pubescent below; sheaths crowded at the base as in species of 
Festuca, those of the culms usually longer than the internodes, ciliate on the margin, 
otherwise glabrous; ligules dense, about 0.3 mm. long; blades 
firm, erect or ascending, 3 to 6 cm., sometimes 8 cm. long, 
about 1.5 mm, wide when flattened out, strongly involute, 
more or less falcate, sometimes strongly so, a few long, stiff 
hairs on the margin toward the base, otherwise glabrous; panicle 
short-exserted, 1.5 to 4 cm. long, nearly as wide, loosely flow- 
F1G.301.—P. breve. From ¢€?ed, the flexuous branches spreading; spikelets 1.3 to 1.4mm. 
type specimen. long, obovate, obtuse, turgid, puberulent; first glume one-third 
to half as long as the spikelet; second glume and sterile lemma 
barely equaling the fruit at maturity; fruit 1.2 mm. long, elliptic. 
Autumnal form erect, branching from the middle nodes, the fascicled branches 
strict, the reduced wiry blades overtopping the panicles. 
Type U. 8. National Herbarium no. 558435, collected April 5, 1906, in ‘‘low pine 
woods between scrub hills, among palmetto,’ Jensen, Florida, by A. 8. Hitchcock 
(no. 734). 
This species is most closely related to P. glabrifolium, from which it is distinguished 
by its short, compact habit, by the 
strongly involute blades bearing long, 
stiff hairs near the base, and by the 
pubescent spikelets. 
DISTRIBUTION. 
Low pine woods and hammocks, east 
coast of southern Florida. 
Fioripa: Indian River, Palmer 
634 in 1874 in part; Jensen, 
Hitchcock 734; Fort Lauder- 
dale, Small & Carter in 
1903; ‘About Boca Ratone Lake, below Delray,’’ Small & Carter in 1903 
(Biltmore Herb.). 
Fia. 302.—Distribution of P. breve. 
Lancearia.— Plants olive green, often purplish; vernal culms usually wiry, minutely 
crisp-puberulent or glabrous; sheaths glabrous or puberulent, at least at the 
summit; ligules nearly obsolete; blades glabrous or puberulent, usually 
strongly ciliate, at least near the base; spikelets unsymmetrically pyriform, 
that is, more swollen on the face than on the back; first glume thin and 
shining, broad at the summit, obtuse or truncate; second glume and sterile 
lemma strongly 7 to 9-nerved, puberulent or glabrous. Species of the At- 
lantic Coastal Plain. 
Spikelets 1.5 to 1.6 mm. long.........--..-----------.------+ 163. P. pauciciliatum. 
Spikelets 2 mm. or more long. 
Blades, or some of them, at least 8 mm. wide; glabrous on 
the upper surface; fruit papillose-roughened. ....-- 166. P. webbertianum. 
Blades not over 6 mm. wide (or if wider, puberulent on 
the upper surface); fruit smooth and shining. 
Spikelets 2.4 to 2.6 mm. long; blades narrowed to- 
toward the base..........-------------------- 167. P. patentifolium. 
