z 
HITCHCOCK AND CHASE—-NORTH AMERICAN PANICUM. 197 
arched about the time the branches appear; the reduced blades more or less involute, 
not exceeding the 1.5 to 4 cm. long panicles; basal blades firm, erect, often as much 
as 5 or 6 cm. long. 
The plant is glabrous throughout with exceptions mentioned; the glaucous olive 
green color and very turgid spikelets, purple-stained at base, are characteristic. 
Harper’s number 408, from Sumter County, Georgia, is doubtfully referred to this ye: 
species. The first glume is very short, = Pence. Ay pe yee Ja) Avo Ca, 
the panicle narrow with few, appressed ; ] 236-4 
branches, and the blades are long and 
narrow. 
DISTRIBUTION. 
Open swampy woods or wet peaty 
meadows, southeastern Virginia to 
Florida and west to eastern Texas. 
-Virainta: Near Norfolk, Kearney 
1514, 2026. 
Nort Carouina: Rose Bay, Ashe 
in 1898; Lake Mattamuskeet, Chase 3203; Roanoke Island, Chase 3240, 3247; 
Wards Mill, Chase 3178. 
Frorma: Baldwin, Combs 60, Hitchcock 987, 998; Mabel, Curtiss 6636; Tampa, 
Hitchcock 9384, 939. 
ALABAMA: Flomaton, Tracy 3625 in part. 
Mississippi: Petit Bois Island, Tracy 4584, Ocean Springs, Tracy 4592. 
Loutstana: Lake Charles, Hitchcock 1144. 
Trxas: Waller, Mitchcock 1174. 
Fig. 198.—Distribution of P. roanokense. 
Y 113. Panicum caerulescens Hack. 
Panicum caerulescens Hack.; Hitche. Contr. Nat. Herb. 12: 219. 1909. ‘The 
type is Hitchcock 706. In glade among Spartina, etc., stretching up through the tall 
grass, Miami, Florida, April 3, 1906, U. S. National Herbarium no. 558380.” This 
specimen consists of two tufts, some of the culms beginning to branch and with over- 
mature primary panicles, and some freely branching. 
DESCRIPTION. 
Vernal form similar to that of P. roanokense; culms more slender, rarely over 75 cm. 
high; blades ascending or spreading, commonly purplish beneath, 5 to 8 cm. long, 4 to 
7 tam. wide, the margins nearly parallel for two-thirds their length; panicles usually 
short-exserted, 3 to 7 cm. long, half as wide or less, the branches narrowly ascending; 
spikelets 1.5 to 1.6 mm. long, 0.9 mm. wide, obovoid, 
blunt, very turgid, glabrous; first glume about one-third 
the length of the spikelets; second glume and sterile lemma 
subequal, the glume scarcely as long as the fruit at ma- 
turity; fruit 1.4 mm. long, 0.8 mm. wide, ellipsoid. 
Autumnal form erect or leaning, sometimes decumbent 
at base, producing short, densely fascicled branches at 
the middle and upper nodes, these tufts scarcely as long 
as the primary internodes, the reduced blades ascending, 
more or less involute, the reduced panicles with a few long-pediceled spikelets. 
This species is distinguished from P. roanokense by the narrow panicles and smaller 
spikelets and by the tufted branches of the autumnal form. 
Fic. 199.—P. caerulescens. 
From type specimen. 
