286 



CONTRIBUTIONS FEOM THE NATIONAL HERBARIUM. 



Panicum scoparium angustifoliuma Vasey, U. S. Dept. Agr. Div. Bot. Bull. 8 : 32. 

 1889. "South Carolina (Dr. Ravenel)" is the first specimen cited. This, which 

 is taken as the type, is in the National Herbarium, and consists of several culms in the 

 early branching state, with mature terminal panicles. 



Panicum scoparium pauciflorum Scribn. Tenn. Agr. Exp. Sta. Bull. 7 : 48. 1894. 

 Based on P. pauciflorum Ell. 



DESCRIPTION. 



Vernal form olivaceous, in loose tufts of few to several culms 35 to 80 cm. high, 

 erect, often purplish, appressed-pubescent, especially below; sheaths shorter than the 

 internodes or the lower longer, the papillose pubescence ascending; hairs of the ligule 

 1 to 2 mm. long, with longer ones intermixed; blades stiffly spreading or ascending, 6 to 

 14 cm. long, 5 to 8 (rarely 10) mm. wide, sharply acuminate, narrowed toward the 

 base, glabrous on the upper surface or rarely with a few long hairs, harshly puberulent 

 beneath, stiffly ciliate near the base; panicles finally long-exserted, 6 to 12 cm. long, 

 about as wide, loosely flowered, branches usually stiffly ascending or spreading; spike- 

 lets long-pediceled, 3.5 to 4 mm. long, 



1.7 to 1.9 mm. wide (smaller in ex- 

 ceptional specimens), oblong-obovate, 

 subacute, sparsely hirsute; first glume 

 less than half the length of the spike- 

 let, acute; second glume slightly shorter 

 than the fruit and sterile lemma; fruit 



2.8 to 3 mm. long, 1.5 to 1.6 mm. wide, 

 elliptic. 



Autumnal form erect or spreading, 

 sometimes topheavy-prostrate, branch- 

 ing sparingly from the lower, freely 

 from the upper, nodes, late in the season 

 the short branchlets aggregated at the 

 summit of the branches, the crowded, 

 reduced blades widely spreading, the panicles more or less included and reduced to a 

 few spikelets, these commonly more turgid and blunt than those of the primary panicle. 

 In this species the spikelets vary more in size than usual in this group. The follow- 

 ing specimens have spikelets only 3.2 to 3.3 mm. long: Bebb 1426, Bu^h 1225, Hitch- 

 cock 1194, Kearney 1386, Reverchon 1840, 4142, and Thurow in 1899. The shape of the 

 spikelets as well as the other characters of these specimens are those of P. oligosan- 

 thes. A few specimens, however, appear to be intermediate between this and P. 

 scribnerianum, having the narrow blades, appressed pubescence, and open, few-flowered 

 panicles of P. oligosanthes, but very turgid, blunt spikelets, which, however, measure 

 3.5 to 3.7 mm. long. These are: Tracy 1754; Bebb 1389 and 2703, Denison, Texas; and 

 Hitchcock in 1903, Wister, Oklahoma (the last two in Hitchcock Herb.). 



Fig. 321. — P. oligosanthes. From type specimen of 

 P. pauciflorum Ell. 



DISTRIBUTION. 



Sandy, usually moist woods. New Jersey to Illinois, south to Florida and Texas, 

 mostly near the coast. 



New Jersey: Atsion, Commons 54. 

 Indiana: Dime Park, Hill 201 in 1898. 

 Illinois: [Wabash Coimty?] Schneck in 1879. 



a This is not based on P. angustifolium Ell. Vasey gives the latter species on page 

 29 of the same paper. 



