176 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
glabrous or with a few cilte toward the base, the short basal blades few or wanting, 
those of the middle culm usually 10 to 15 cm. (sometimes only 5 to 6 cm.) long, 3 to 5 
mm. wide; panicles finally long-exserted, 5 to 9 cm. long, narrow, the flexuous branches 
narrowly ascending, rarely loosely spreading, the branchlets appressed, the short- 
pediceled spikelets more or less secund along the 
branches; spikelets 2 mm. long, 1.2 mm. wide, 
broadly obovate, blunt, the attenuation at base 
short; first glume about one-third the length of the 
spikelet, truncate or pointed; second glume and 
sterile lemma scarcely equaling the fruit at maturity, 
finely papillose-pubescent; fruit 1.8 mm. long, 1.1 
mm. wide, elliptic, puberulent at the subacute 
Fig. 170.—P. neuranthum. From apex. : 
type specimen. Autumnal form with erect, usually slender culms 
nearly as tall as the vernal form; blades involute 
but not stiff, not conspicuously shorter than the vernal blades, 4 to 10 cm. long; 
spikelets more turgid, the fruit often slightly exceeding the second glume. 
Most nearly related to P. ovinum, from which the vernal form may be distinguished 
by the narrower, fewer-flowered panicles with subsecund, slightly smaller spikelets, 
by the usually taller culms, and by the absence of the comparatively broad basal blades 
which distinguish the latter; the au- 
tumnal form is much taller, with 
longer, less crowded blades. From 
P. aciculare this is distinguished by 
absence of pubescence, much longer 
blades, subsecund spikelets, and an 
erect autumnal form. 
DISTRIBUTION. 
Savannas and open ground, southern bs 
Florida, and along the coast to Missis- Fic. 171.—Distribution of P. neuranthum. 
sipp1; also in the Bahamas and Cuba. 
Fiorma: Miami, Hitchcock, 109, 705, 710; ies Harbor, Tracy 7176; Sanibel 
Island, Simpson 298; Cleannnatien Tracy 7166; Braidentown, Tracy 6711; 
without locality, Rugel 290. 
Mississippi: Petit Bois Island, Tracy 4567; Horn Island, Tracy 2859. 
Banamas: New Providence, Britton & Brace 599 (Field Mus. Herb.). 
CuBa: Eastern Cuba, Wright 3453 in part. 
Bicknelliana.—Culms few to several in a tuft, glabrous or nearly so; sheaths glabrous 
or with a few hairs; ligules nearly obsolete; blades somewhat elongated, 
stiffly ascending or spreading, ciliate at base; panicles few-flowered, with 
7-nerved, long-peduncled spikelets 2.5 to 3 mm. long. Autumnal form 
sparingly branching from the upper or middle nodes. 
This group of two species is intermediate in habit between the Depauperata 
and Dichotoma; the blades are elongated as in the former but the vernal 
culms and the mode of branching are more like those of the latter. 
Spikelets 2.5 to 2.8 mm. long, blades not over 9 mm. wide.... 99. P. bicknellii. 
Spikelets 3 mm. long, blades as much as 12 mm. wide...-....- 100. P. calliphyllum. 
