196 



CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Delaware: Wilmington, Chase 3616. 



Maryland: Little Falls, Vasey in 1884; Cabin John 



Chevy Chase, Chase 2946, 



Hitchcock 361. 

 District of Columbia: House 911, 



Kearney 28 in part. 

 Virginia: Arlington, Chase 2964. 

 North Carolina: Raleigh, Ashe 



in 1895, Chapel Hill, Chase 



3059,3061,3072; Jacksonville, 



Chase 3192. 

 South Carolina: Orangeburg, 



Hitchcock 6, 1416J. 

 Georgia: Dublin, Harper 1349. 

 Tennessee: Sumner County, Gat- 



tinger in 1883 (Univ. Tenn. Herb.). 

 Alabama: Tensaw, Tracy 8029. 

 Louisiana: Lake Charles, Hitchcock 1164. 



112. Panicuin roanokense Ashe. 



Chase 2853, 3772; West 



Fig. 196.— Distribution of P. yadkinense. 



Panicum roanokense Ashe, Journ. Elisha Mitchell Soc. 15: 44. 1898. "Type 

 material collected by writer in dry soil, Roanoke Island, N. C. June, 1898. Also 

 collected at Rose Bay and Mackleyville, N. C, the same month." The type could 

 not be found in Ashe's herbarium. In the Biltmore Herbarium is a specimen from 

 Manteo, Roanoke Island, N. C, collected by Ashe, June 10, 1898, and labeled by him 

 Panicum roanokense Ashe. This is a duplicate type or possibly the type. It con- 

 sists of two vernal culms with mature primary panicles. 



Panicum curtivaginum Ashe, Journ. Elisha Mitchell Soc. 16: 85. 1900. "Collected 

 at Petit Bois Island, Mississippi, May 8, 1898 by S. M. Tracy." An unmounted 

 specimen of the collection cited was found in a cover marked "P. curtivaginatum sp. 

 nov." in Ashe's herbarium. No name was written on the Tracy label, which bears 

 the number 4584. As this was the only specimen of this collection found in Ashe's 

 herbarium it is taken as the type. It consists of a tuft of three slender vernal culms 

 with over-mature panicles. The autumnal form is not represented, but in a specimen 



of Tracy 4584 in the National Herbarium the autumnal 



culms of the previous year are attached to the tuft. 



The spikelets are described as "quite 1.5 mm." long, 



but they measure 2 mm. 



description. 



Vernal form cespitose, somewhat glaucous olive 

 green; culms erect or ascending, 50 to 100 cm. high! 

 sheaths half as long as the internodes or less, gla- 

 brous, or the lowermost sometimes sparsely pubescent; 

 blades at first stiffly erect, later ascending or spread- 

 ing, 6 to 9 cm. long, 3 to 8 mm. wide, tapering to both ends, glabrous or with a 

 few hairs around the base; panicles 4 to 8 cm. long, scarcely as wide, the branches 

 spreading; spikelets 2 mm. long, 1 mm. wide, ellipsoid-obovoid, very turgid, glabrous; 

 first glume about one-third the length of the spikelet; second glume and sterile lemma 

 strongly nerved, subequal, the glume rather conspicuously purple-tinged at base, 

 scarcely covering the fruit at maturity; fruit 1.6 mm. long, 0.9 mm. wide, ellipsoid. 

 Autumnal form erect or decumbent, branching at the middle and upper nodes, the 

 branches numerous but not in tufts, the primary internodes elongating and becoming 



Fig. 19 7.— P. roanokense. From 

 specimen collected by Ashe at 

 Rose Bay. 



