25 
lets oblong, about 1 line long, obtusish; empty glumes, mostly two (the lower one 
often wanting), pubescent, both equaling the flower.—In cultivated and waste 
grounds, less common than the following. Var. MISSISSIPPIENSIS Gattinger. Taller 
(6 to 20 inches high), spikes longer (14 to 34 inches), spikelets acutish.—Vicinity of 
Nashville, Tenn. (Dr. Gattinger). 
2. P. sanguinale Linn. (CRaB-GRASS). (Gray’s Manual, 6th ed., p. 630.) Culm 
erect or decumbent, usually rooting at the lower joints, leaves and sheaths smooth or 
hairy, variable in length and breadth; spikes 3 to 10 or 15, spreading, digitate or ap- 
proximate, 3 to 6 inches long; spikelets oblong-lanceolate, about 1} lines long, acute, 
smoothish, pubescent; first glume minute, second half to two-thirds as long as the 
spikelet, third equaling the spikelet.—Naturalized every where. 
Var. CILIARE Vasey Proc. Am. Acad. xxiv. p. 80, (P. ciliare Retz). Glumes ciliate- 
fringed. 
Var. SIMPSONI Vasey n. var. With the general habit of P. sanguinale, but peren- 
nial; culms 2 to 3 feet long, from long-rooting rhizomes; spikes about 8, each 5 to 6 
incheslong; spikelets about 14 lines long; empty glumes two, equal, smooth,7-nerved, 
acuminate.—Manatee, Fla. (J. H. Simpson), and Mississippi (S. M. Tracy). 
3. P. filiforme Linn. (Gray’s Manual, 6th ed., p. 630), (Digitaria filiformis Muhl.) 
Culms very slender, 1 to 3 feet high, erect, simple, or sparingly branched; leaves 
narrowly linear, 3 to 10 inches long, erect, somewhat pubescent, and with sheaths 
hairy; spikes 2 to 8, erect or somewhat spreading, 2 to 6 inches long; spikelets 1 
line long or less, oblong, acute; empty glumes two, the lower slightly shorter and 
the upper equalling the flower.—Sandy or gravelly ground; Maine to Florida and 
westward. 
4. P. serotinum Trin. (Chapm. Fl. 8. States, Suppl., p. 666), (Digitaria sero- 
tina Michx.; D. villosa Ell.) Perennial, extensively creeping, much branched, making 
a thick carpet; flowering culms 6 to 10 inches; leaves short, erect, hairy, 1 to 24 
inches long, sheaths villous; spikes 3 to 5, about 2 inches long, varrow; spikelets 
less than 1 line long, acute; two empty giumes, the first one-quarter to one-third as 
long, and the second nearly as long, as the spikelet.—North Carolina to Florida and 
westward. 
§ 2. TRICHACHNE Benth. 
5. P. leucophzum H. B. K. Nov. Gen. I. p. 97. Culms stout, 2 to 4 feet high, 
erect; leaves broadly linear, 1 foot long, scabrous above, ligule ciliate ; panicle race- 
mose, contracted, dense, 6 to 10 inches long; the simple branches numerous, erect, 
fasciculate, 2 to 4 inches long; spikelets linear-lanceolate, acuminate, about 2 lines 
long; lower glume minute, second nearly as long as, and the third equalling, the 
perfect flower, which is linear-lanceolate and mucronate-pointed.—Low, rich ground, 
South Florida (Chapman, Curtiss, etc.). 
6. P. lachnanthum Torr. Culms rather slender, 2 to 3 feet high; leaves much 
narrower and shorter, panicle shorter, more slender, with fewer and shorter spikes ; 
spikelets smaller, 1 to 14 lines long, ovate-lanceolate, the perfect flower ovate-lanceo- 
late, acute and mucronate-pointed—mostly on dry hills, Texas, Arizona and New 
Mexico. 
§ 3. SuBsPICATA Vasey. 
7. P. paspaloides Pers. (Chapm. Fl. 8. States, Suppl, p. 666.) Culms 2 to 3 
feet high, decumbent and rooting below, smooth, stout, leafy ; leaves narrow, 6 to LO 
inches long, becoming somewhat involute, and with the sheaths smooth;. panicle 5 
to 10 inches long, strict, of 10 to 20 appressed, sessile, simple branches, the lower 
ones 1 to 1}inches long, upper gradually shorter; spikelets ovate-oblong, obtusish, 
smooth, 1 to 1} lines long, imbricate in two rows on the narrow axis; the lower glume 
truncate-obtuse, one-third as long, and second glume two-thirds as long as the spike- 
lets (also thin and obtuse).—In ditches or water, Florida to Texas and Mexico. 
8. P. Curtisii Chapm. Fl. 8. States, p. 573. Culms 3 to 4 feet high, often 
