Bulbostylis tenuifolia (Rudge) J. F. Macbr.

Bulbostylis tenuifolia (Rudge) F. Macbr. Field Mus
Publ. Bot. 11: 5. 1931.
Scirpus tenuifolius Rudge, PI. Guian. 18. 1805.
Isolepis bufonia H.B.K. Nov. Gen. & Sp. 1 : 222. 1816. (Type from Venezuela.)
Scirpus biifonis Poir. in Lam. Encyc. Suppl. 5 : 105. 1817.
Oncostylis tenuifolia Nees in Mart. Fl. Bras. 2^: 83. 1842.
Bulbostylis capillaris var. tenuifolia Clarke, Symb. Ant. 2: 89. 1900.
Chiefly annual ; culms capillary, 0.5-2.0 dm. high, sulcate, glabrous, rarely hirtellous ; leaves capillary, shorter than the culms, the stramineous sheaths lightly fimbriate at the apex; inflorescence a simple or compound umbel, the spikelets mostly long-pedicellate and solitary at the ends of the frequently arcuate branches ; spikelets narrowly ovate, Z-6 mm. long, frequently acute ; scales dark brown with a lighter keel, glabrous to hirtellous, usually obtuse to acute, rarely mucronate; achenes trigonous, obovate, 0.6-0.8 mm. long, finely spinescent-papillose (occasionally reticulate to nearly smooth), stramineous to grayishbrown, often with concave faces ; tubercle reddish-brown, minute ; style slender, 0.75 mm. long below the branches; stamen 1, the anther 1.0 mm. long.
Type locality : French Guiana.
Distribution: Chiefly northern South America; also scattered in Cuba (C. Wright 3382); El Salvador (Calderon 1413) ; Guatemala {Heyde & Lux 3888) ; Consoquitla, Mexico {Liebmann) ; Panama (Standley 26353).