158 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Laxiflora.—Plants light green, vernal culms 10 to 40 cm. high, numerous in tufts; 
blades flat, soft, mostly ciliate, basal blades shorter, but not forming true 
rosettes in theautumn; ligules nearly obsolete; primary panicles long-exserted; 
spikelets 1.3 to 2.3 mm. long, obovate, obtuse, turgid, 5 to 7-nerved. 
Autumnal form freely branching near the base, forming close, flat, soft tufts, 
the reduced panicles often exceeded by the leaves. 
Sheaths retrorsely pilose; spikelets papillose-pilose. 
Panicle branches ascending, forming a rather compact 
panicle; spikelets 1.6 mm. long.............-..... 87a. P. xalapense stric- 
tirameum., 
Panicle branches loosely spreading. 
Blades ciliate and more or less pilose on the surface; 
spikelets 2 mm. long. .................-...-. 87. P. xalapense. 
Blades glabrous or nearly so on the surface and mar- 
gin, spikelets 2.2 mm. long.................. 86. P. laxiflorum. 
Sheaths not retrorsely pilose; spikelets pubescent or glabrous. 
Spikelets pubescent, about 2 mm. long.................. 88. P. ciliatum. 
Spikelets glabrous. 
Blades glabrous on the surface. ...............2.... 89. P. polycaulon. 
Blades pilose on the surface.........2.............. 90. P. strigosum. 
86. Panicum laxiflorum Lam. 
Panicum laxiflorum Lam. Encycl. 4:748.1798. ‘‘Cette plante est dans l’herbier du 
Muséum. Je la crois d’Amérique Septentrionale.’’ The type, labeled in Lamarck’s 
hand “‘panicum laxiflorum lam. dict.,’’ is in the Lamarck Herbarium. It consists of 
two culms, each with a loose terminal panicle, one leafless, the other with a single 
blade glabrous on both surfaces; the spikelets are 2.2 mm. long, papillose-pilose, the 
fruit covered by the second glume and sterile lemma. These characters indicate not 
the species that has been called by this name in America, but the one of more restricted 
southern range. 
Panicum pyriforme Nash, Bull. Torrey Club 26: 579.1899. ‘‘Type collected by the 
writer in clay soil, at Orange Bend,@ Lake Co., Florida, March 12-31, 1894, no. 239.” 
The type, in Nash’s herbarium, consists of a clump of three culms, 15 to 45 cm. high. 
The description states that the blades are glabrous 
on the margin, but the type, as well as duplicate 
types in the National and Columbia University 
herbaria and in Hitchcock’s herbarium, has sev- 
eral sparingly ciliate blades; the spikelets are said 
to be “‘about 2.5 mm. long” but measure 2.2 mm. 
Panicum aureum Muhl.; Scribn. & Merr. U.S. 
Dept. Agr. Div. Agrost. Cire. 27:4. 1900. This 
is mentioned as a synonym of P. lazxiflorwm Lam. 
The type specimen is in the Muhlenberg Herba- 
rium in folio ‘‘187, Panicum strigosum.’’ It is labeled ‘‘117 P. aureum M 115.”’ 
Fia. 144.—P. laziflorum. From 
type specimen. 
DESCRIPTION. 
Vernal form with slender culms 20 to 60 cm. high, erect, or the lower nodes often 
geniculate, glabrous; nodes bearded with reflexed hairs; sheaths shorter than the 
internodes, conspicuously retrorsely pilose; blades mostly 10 to 18 cm. long, 7 to 12 
mm. wide, acuminate, narrowed toward the base, glabrous on both surfaces and on 
“The locality of Nask 239 as given on the label is ‘‘vicinity of Eustis.’’ Orange 
Bend is a few miles northwest of Eustis. 
