No. 32. 

 CHLORIS GLAUCA Vasey. 



Plant annual, entirely glabrous. 



Culm single, erect, 2 to 4 feet high, glabrous, unbranched. 



Leaves of the root numerous; sheath very closely compressed, equitant, widely 

 diverging, about 3 lines wide when folded, 8 inches or less long, continuing into 

 the blade with a mere slight contraction at the mouth; blade folded below, flat 

 above, keeled, 3 to 4 lines wide,4to 12 inches long, abruptly obtuse at the apex; second, 

 third, and usually fourth iiiternodes of the culm very short, their leaves similar to 

 those of the root and appearing to start from the first node of the stem. Suc- 

 ceeding leaves 1 or 2, with longer close sheaths; blade nearly wanting. 



Inflorescence an erect, pedunculate, iimbellate cluster of 8 to 15 spikes. Spikes 

 3 to 5 inches long; rachis triangular, scabrous; this and the first and second glumes 

 greenish straw-color, remainder of the spikelets very dark brown or black. 



Spikelets in 2 rows on one side of the rachis, inserted alternately, those in 

 each row at intervals of about line, 1 line long. 



Glumes 4; first f line long, ovate-lanceolate, acute, insequilateral, with 1 

 rigid scabrous nerve; second 1 line long, linear, notched at the apex, nerved 

 like the first, nerve produced into a short deflexed scabrous mucro, mucros sec- 

 und along the edge of the spike; third (flowering) glume compressed, scabrous 

 toward the apex, each half oblong, acute; fourth (sterile) glume obovate, truncate, 

 scabrous along the upper margin, rolled into a tube. 



Flower single, hermaphrodite. Palet oblanceolate-oblong, notched at the 

 acute apex, 2-nerved, with additional inflexed membranaceous margins. Stamens 3 ; 

 anthers oblong-linear, \ line long, notched at the apex. Stigmas short cylindrical. 



Grain oblong, acute at either end, triangular in cross-section ; rachilla disar- 

 ticulating above the second glume. 



Plate XXXII ; a and b, spikelet opened to show the parts; rachilla broken at 

 the point of disarticulation. The leaf belonging to the uppermost node of the 

 stem is not shown. 



NOTE. This species was inserted here, by mistake, instead of Chloris Swart- 

 ziana Doell. (Chloris petrc&a Swz.), which occurs in Texas near the coast. It is 

 much less robust, with narrower leaves, fewer spikes (3 to 5), and some difference 

 in the flowers. It is possible, however, that both species may occur, although 

 Chloris glauca is principally known from Florida. 



