310 



CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Louisiana: Rayville, Ball 25; Lake Charles, Chase 4430, 4437, Hitchcock 1142; 



Plaquemines Parish, Langlois 41 in part. 

 Texas: Waller, Hitchcock 1207, 1208, Thurow in 1898; Houston, Ball 828 (Gray 



Herb.)- 

 Mexico: Cordoba, Bourgeau in 1866 (Paris Herb.). 



187. Panicum equilaterale Scribn. 



Panicum equilaterale Scribn. U. S. Dept. Agr. Div. Agrost. Bull. 11: 42. pi. 2. 1898. 

 Two specimens are cited as follows: "In pine lands [Eustis], Florida (No. 1120, George 

 V. Nash, June, 1894); scrubby hammock lands [Eustis], Florida (No. 1674, George V. 

 Nash, August, 1894)." The plate cited above is drawn from Scribner's specimen of 

 Nash 1674, now in Hitchcock's herbarium, which specimen is therefore the type. It 

 consists of two culms 53 and 65 cm. high, one simple, the other producing short fas- 

 cicled branches at the upper two nodes. The blades are 10 to 17 cm. long. 



Panicum epilifolium Nash, Bull. Torrey Club 26: 571. 1899. "The type col- 

 lected by the writer in a scrub hammock at Eustis, Lake Co., Florida, March 12-31, 

 1894, no. 45." Th« type, in Nash's herbarium, is the vernal form, with scarcely 

 mature panicles. The longest blade is but 7.5 cm. long, but a duplicate specimen in 

 the National Herbarium has blades as much as 10 cm. long. Two species were dis- 

 tributed under Nash's no. 45, the other being P. commutatum. 



DESCRIPTION. 



Vernal plants glossy, grayish green, in clumps of several to many culms, these 25 to 70 

 cm. high, stiff and erect, glabrous or nearly so, including the nodes; sheaths much 

 shorter than the elongated internodes, or the upper two approximate, glabrous except for 

 the densely short-ciliate margin; ligules nearly obsolete; blades firm, widely spreading 

 or ascending, 6 to 17 cm. long, 6 to 14 mm. wide, very scabrous (the margins nearly 

 parallel), often ciliateat the rounded orsubcordate base, acuminate, glabrous on both 



surfaces, often drying conduplicate; panicles 

 usually short-exserted, loosely flowered, 5 to 

 10 cm. long, two-thirds to three-fourths as 

 wide, the branches ascending; spikelet 3.2 

 mm. long. 1.3 mm. wide, obovate-elliptic, 

 obscurely pointed, pubescent; first glume half 

 the length of the spikelet or more, rather 

 remote, triangular, acute; second glume and 

 sterile lemma subequal, barely covering the 

 fruit at maturity; fruit 2.6 to 2.7 mm. long, 

 1.25 mm. wide, elliptic, minutely umbonate. 

 Autumnal form erect or leaning, branching 

 from the upper and middle nodes after the 

 maturity of the primary panicle, these primary branches often longer than the inter- 

 nodes and producing short, fascicled, appressed branchlets with reduced spreading 

 blades from their uppermost nodes, the numerous small panicles partly included; 

 winter rosette appearing late, the blades lanceolate, firm, sometimes ciliate. 



This species is distinguished from P. commutatum by its almost linear blades, which 

 vary much in size but are characteristically parallel-margined, and by its branching 

 from the uppermost nodes of both the primary culm and the branches; and from P. 

 manatense, which branches in the same way, by the erect habit and rather distant 

 first glume half as long as the spikelet. 



Fig. 350.— P. equilaterale. From type specimen. 



