No. 23. 



CHLORIS SWARTZIANA Doll. (Chloris petrcea Swz. lion. Thunb.) 

 (Schidtesia petrcea, Spreng. ) (? Eustachys petrcea Desv. ) 



Plant perennial, from short rootstock, light green or more or less purplish 

 throughout. 



Culm erect, or genticulate and spreading below, frequently branched, flatly 

 compressed, smooth, 1 to 2 feet tall. 



Leaves; radical, with closely compressed, smooth, equitant, divergent sheaths, 

 and flat or folded blades, round-pointed, scabrous on the edge, 2 lines wide, 4 to 

 10 inches long; of stem 3 *o 5, sometimes opposite; sheaths compressed, loose, 

 smooth, shorter than internodes; lower blades like those of radical leaves but 

 shorter, and upper ones reduced to nearly none; ligule a minute, ciliate, membrana- 

 ceous fringe. 



Inflorescence a digitate cluster of 3 to 6 sessile, linear, erect, slightly spreading 

 spikes, 2 to 3 inches long, bearing the crowded sessile spikelets in two rows on one 

 side of the slender, scabrid rachis. 



Spikelets 2*-flowered, upper flower sterile; first glume broadly ovate-acute, 

 smooth, 1-nerved, scarious, \ line long; second glume obovate, 2 minutely toothed 

 lobes at apex and a short hispid awn formed by the excurrent nerve, hispid on back, 

 f to 1 line long; floral glume, rotund, broadly acute, or rounded and mucronate, 

 coriaceous, brown, ciliate, pubescent on the lower two-thirds of the single nerve, 

 smooth above; palet ovate-lanceolate, convex, obscurely 2-nerved, 1 line long; ster- 

 ile flower a broadly ovate, truncate glume, folded triangular, brown, | line long. 



Grain translucent, creamy-white, triangular. 4- line long, falling with spikelet 

 intact except the empty glumes which are left on the rachis. 



Plate XXIII; a, spikelet; b, floral glume, sterile flower, stamens and stigmas; 

 c, second empty glume; d, first empty glume; palet not shown. 



Low grounds near the Gulf, from Florida westward to Texas. 



