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 458, from Sumter County, Georgia, is doubtfully referred to this 

 species. The first glume is very short, 

 the panicle narrow with few, appressed 

 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. 



Virginia: Near Norfolk, Kearney 



1514, 2026. 

 North Carolina: Rose Bay, Ashe 



in 1898; Lake Mattamuskeet, Chase 3203; Roanoke Island, Chase 3240, 3247; 



Wards Mill, Chase 3178. 

 Florida: Baldwin, Combs 60, Hitchcock 987, 998; Mabel, Curtiss 6636; Tampa, 



Hitchcock 938£, 939. 

 Alabama: Flomaton, Tracy 3625 in part. 



Mississippi: Petit Bois Island, Tracy 4584, Ocean Springs, Tracy 4592. 

 Louisiana: Lake Charles, Hitchcock 1144. 

 Texas: Waller, Hitchcock 1174. 



113. Panicum caerulescens Hack. 



Panicum caerulescens Hack.; Hitchc. 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. 



Fig. 198.— Distribution of P. roanokense. 



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 mm. 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. 



Fig. 199. — P. caerulescens. 

 From type specimen. 



