2. Fimbristylis Interior Britton, N. Sp. Plains Fimbristylis

Fig. 785

Perennial, with short stolons, the base of the culm slightly thickened. Culms loosely tufted to solitary, very slender, smooth, striate, somewhat compressed, 1°-2° high; leaves rough-margined, involute, at least toward the tip, 1" wide or less, shorter than the culms; bracts of the involucre mostly shorter than the umbel, ciliate; umbel a little compound, its rays filiform; spikelets few to several, ovoid to ovoid-oblong, acutish, 5" long or less, many-flowered; scales yellow-brown, ovate, striate, mucronate or the lower ones awned, glabrous, dull; stamens 3; achene broadly obovate, blunt, cancellate in many rows, chestnut-brown, nearly \" long.

Colorado and Nebraska to Texas. Type collected by Geo. E. Osterhout at Sterling, Logan County, Colorado, Aug. 13, 1896.

3. Fimbristylis Puberula (Micbx.)Vahl. Hairy Fimbristylis

Fig. 786

Scirpus pubcrulus Michx. Fl. Bor. Am. 1: 31.

1803. F. pubcrula Vahl, Enum. 2: 289. 1806.

Perennial by stout rootstocks, culms slender, 3-angled, 8-2° tall, usually exceeding the leaves. Leaves involute, less than 1" wide when unrolled, often more or less pubescent, their sheaths green; leaves of the involucre 2-4, short; umbel simple or compound, the rays ¥-2' long; central spikelets sessi e; spikelets oblong, obtuse or subacute, 3"-5" long, 1"-1 1/2" in diameter; scales thin, brown with a lighter midvein, broadly oblong or nearly orbicular, dull, puberulent, obtuse or mucronate; stamens 2-3; style 2-cleft; achene obovate or oblong, biconvex, pale brown, longitudinally striate and reticulated.

Fields and meadows, southern New York to Florida and Louisiana. Also from Ontario, Michigan and Illinois to Kansas and Texas. Mistaken in our first edition for F. castanea. July-Sept.

4. Fimbristylis Baldwiniana Torr Weak Fimbristylis

Fig. 787

F. Baldwiniana Torr. Ann. Lye. N. Y. 3: 344. 1836.

Annual, roots fibrous, culms slender, flattened, striate, densely tufted, erect or ascending, 2'-15' long, usually longer than the leaves. Leaves flat, about \" wide, glabrous or sparingly ciliate, pale green and appearing glaucous, those of the involucre 3-5, one of them often exceeding the umbel; umbel simple or slightly compound, the central spikelet sessile; spike-lets ovoid or ovoid-oblong, 3"-6" long, about 1" in diameter; scales ovate, thin, pale greenish-brown, subacute or mucronulate; stamen 1; style 2-cleft, pubescent; achene biconvex, obovoid, light brown, longitudinally ribbed, the ribs tubercled and connected by very fine cross-lines.

In moist soil, southern Pennsylvania to Florida, west to Illinois, Missouri and Texas. Included in our first edition in the southern and tropical American F. laxa Vahl. July-Sept.