HITCHCOCK AND CHASE NOETH AMEKICAN PANICUM. 



295 



Panicum laxiflorum pubescens Chapm. Fl. South. U. S. ed. 3. 586. 1897, notVaeey 

 1892. Based on Panicum pubescens Lam., though the description applies to P. strigo- 

 sum Muhl., the species referred by Chapman to this variety. 



Fig. 333. — P. scoparium. From type specimen of 

 P. viscidum Ell. 



DESCRIPTION. 



Vernal plants grayish olive green, velvety-pubescent throughout except as noted; 

 culms 80 to 130 cm. high, stout, erect or ascending, usually geniculate at base, the 

 nodes villous with reflexed hairs, a glabrous, viscid ring below; sheaths about half as 

 long as the long internodes, the velvety pubescence wanting on the back toward the 

 summit, the surface here viscid when fresh; ligules 1 mm. long; blades rather thick, 

 ascending or spreading, often reflexed late in the season, 12 to 20 cm. long, 10 to 18 mm. 

 wide, long-acuminate, slightly narrowed to the rounded base, the uppermost leaf often 

 much reduced; panicles finally long-exserted, 8 to 15 cm. long, nearly as wide, many- 

 flowered, the axis, branches, and pedicels with viscid blotches, the branches ascend- 

 ing or spreading, spikelet-bearing to the base; spikelets 2.4 to 2.6 mm. long, 1.4 to 1.5 

 mm. wide, obovate, turgid at maturity, abruptly pointed, papillose-pubescent with 



spreading hairs ; first glume one-fifth to 

 one-fourth the length of the spikelet, 

 acute to truncate; second glume and 

 sterile lemma strongly nerved, the 

 glume obtuse, shorter than the fruit at 

 maturity, the lemma abruptly pointed 

 and equaling it; fruit 2 mm. long, 1.4 

 mm. wide, obovate-elliptic, apiculate. 



Autumnal form leaning or spreading, 

 branching from the middle nodes after 

 the maturity of the primary panicle, 

 the branches usually longer than the 

 primary internodes, repeatedly branching, often more or less scorpioid, the ultimate 

 branchlets in flabellate fascicles, the sheaths often swollen toward the summit, con- 

 tracted at the throat, the blades much reduced, overtopping the small, partially 

 included panicles. 



A well-marked and constant species, easily recognized by its velvety pubescence, 

 the glabrous, viscid ring below the nodes, and the viscid upper portion of the sheath. 

 The viscidity disappears in drying, but the glandular surface is evident. 



DISTRIBUTION. 



Wet or damp soil, Massachusetts to Florida, west to Oklahoma and Texas; also in 

 Cuba. 



Massachusetts: Cape Cod, Cheney in 1903 (N. E. Bot. Club Herb.). 



New Jersey: Avon, Mackenzie 1854; Tuckerton, Chase 3600; Wildwood, Chase 



3486. 

 Pennsylvania: Tinicum, /Smii^ 159; without locality, McMinn. 

 Delaware: Millsboro, Commons2?>; Ellendale, Commons 2,2. 

 Maryland: Eastern Shore, Canby; Anne Arundel County, /. D. Smith in 1879; 



Chesapeake Junction, Hitchcoch 1637. 

 District of Columbia: Kearney in 1897, Merrill 233, Sheldon in 1881, Steele in 



1896 and 1897, Topping in 1895, Vasey in 1881, Fare? in 1878 and 1879. 

 Virginia: In the vicinity of Cape Henry, Chase 5438, Coville 17, Hitchcoch 593, 



Kearney 308, 1477, Mackenzie 1688, Noyes 88, 89; Dismal Swamp, McCarthy 



in 1883. 

 North Carolina: Wilmington, Biltmore Herb. 4290; Hickory, Small & Heller in 



1891; Heiligs Mill, Smxill dc Heller 204; West Raleigh, Coit 1304. 



