Eustachys petraea (Sw.) Desv.

Chloris petraea Sw. Prodr. 25. 1788
lAira aegilopsoides Walt. FI. Car. 78. 1788. (Type from South Carolina.)
Agroslis complanata Ait. Hort. Kew. 1: 96. 1789. (Type grown in England, seed from Jamaica.)
Eustachys petraea Dcsv. Nouv. Bull. See. Philom. 2: 189. 1810. (Based on Chloris petraea Sw.)
SchuUesia petraea Spreng. Pug. 2: 17. 1815. (Based on Chloris petraea Sw.)
Aira complanata Ait.; Steud. Nom. Bot. ed. 2. 1: 44, as synonvm of Chloris petraea Sw. 1840.
Chloris Swarlzii C. Miill. Bot. Zeit. 19: 341. 1861. (Based on C. petraea Sw.)
Chloris septentrionalis C. Miill. Bot. Zeit. 19: 340. 1861. (Type from Rio Brazos, Texas, Drum-
mond.) Chloris Swartziana Doll, in Mart. FI. Bras. 23; 68. 1878. (Based on C. petraea Sw.)
Perennial; culms erect or sometimes decumbent at the base and rooting at the lower nodes, 30 cm. to more than a meter tall, conspicuously flattened; sheaths broad, flattened and keeled, crowded at the base in a fan-shaped cluster; ligule very short, minutely ciliate; blades conduplicate at the base, becoming flat toward the obtuse tip, 4-20 cm. (mostly about 10 cm.) long, 4-8 mm. wide, glabrous or densely pubescent on the upper surface at the very base; spikes 2-7 (usually 4-6), 3-12 cm. (mostly 6-8 cm.) long, digitate, narrowly ascending; spikelets 2 mm. long, horizontally spreading; glumes l-nerved, scabrous on the keel, the first 1.2 mm. long, acute, crescent-shaped, the second a little longer, broader, obtuse, notched, with an awn 0.5-1 mm. long; fertile floret dark-brown, 1.8 mm. long, the callus very short and rounded, the lemma obovate, blunt, pubescent on the keel, sparsely short-hispid on the upper half of the margins, the tip scabrous, the internerves smooth and shining, awnless; rudiment oblongtruncate, about 1 mm. long, 0.5 mm. wide, the tip scabrous.
Type locality : Jamaica (Swariz) .
Distribution: Open sandy ground, usually near the coast, Southeastern United States, eastern Mexico, and the West Indies, and southward to Trinidad and Panama.