200 



CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



DESCRIPTION. 



Fig. 203.— P. sphagnicola. 

 type specimen. 



From 



Vernal form grayish olive green, cespitose; culms slender, strongly flattened, erect, 

 or reclining, 50 to 100 cm. high; sheaths glabrous or the lowermost sparsely papillose- 

 pilose, soon becoming divaricate and enveloping the internodes only at base; blades at 

 first erect, later widely spreading, glabrous, 5 to 8 cm. long, 3 to 7 mm. wide; panicles 



narrow, 5 to 6 cm. long, the branches ascending 

 or somewhat spreading, not spikelet-bearing at 

 the base; spikelets 2.5 mm. long, 1.1 mm. wide, 

 elliptic ; first glume nearly half the length of the 

 spikelet, subacute; second glume and sterile 

 lemma strongly nerved, minutely pubescent to- 

 ward the summit or glabrous, the glume shorter 

 than the fruit; fruit 2 mm. long, 1 to 1.1 mm. 

 wide, elliptic, subobtuse. 



Autumnal form decumbent or finally prostrate- 

 spreading, divaricately branching from all the 

 nodes, the branches slender and elongated, some- 

 times rooting at the nodes; sheaths divaricately spreading from the stem, usually 

 nearly as long as the blades; blades flat, reduced in length but not much in width, 

 mostly 1 to 2 cm. long, or on the ultimate branchlets only 5 mm. long and 1 mm. 

 wide; panicles rather few, reduced to a few short-pediceled spikelets; basal blades 4 

 to 8 cm. long, about 1 cm. wide, sometimes sparsely pilose at base. 



This species is readily distinguished in the autumnal form by its slender, widely- 

 spreading branches and divaricate sheaths. At this stage the primary sheath may 

 subtend two branches, each with its conspicuous prophyllum, 5 to 15 mm. long, 

 ciliate on the keels and bearing a tuft of hairs at the acuminate tip. The leaf of the 

 second branch is much reduced and inclosed in the base of the primary sheath. 

 Panicum lucidum, the only other spe- 

 cies with a like autumnal habit, is 

 much more slender, more leafy, and 

 bright green and shining, and has 

 smaller long-pediceled spikelets. 



DISTRIBUTION. 



Edges of cypress swamps, in sphag- 

 num bogs, and in similar moist, shady 

 places, southern Georgia and Florida. 

 Georgia: Darien, Biltmore Herb. 



5066 e (Biltmore Herb.). 

 Florida: Lake City, Bitting 18, Combs 73, Hitchcock 1006, Nash 2500; Sanford, 

 Chase 4039; Levy County, Combs 838; eastern Florida, Palmer 633 in 1874 

 (Gray Herb.). 



Fig. 204.— Distribution of P. sphagnicola. 



Spreta. — Culms tufted, rather stiff, mostly glabrous or nearly so; ligules densely 

 hairy, 3 to 5 mm. long; blades not over 8 mm. wide; spikelets 1 to 1.6 mm. 

 long, pubescent or rarely glabrous, second glume and sterile lemma 5 to 

 7 nerved. Autumnal form with more or less tufted branchlets and much 

 reduced leaves and panicles. 



Panicle narrow, one-fourth to one-third as wide as long 116. P. spretum. 



Panicle open, two-thirds as wide as long, or more. 



Spikelets 1.5 mm. long 117. P. lindheimeri. 



