No. 31. 

 CHLORIS CUCULLATA Bischoff. 



Plant annual. 



Culms erect, at the base procumbent, 9 to 24 inches high, somewhat compressed 

 or nearly terete, glabrous, branched only at the base. 



Leaves of the root numerous ; sheaths 3 inches long or less, glabrous, compressed, 

 glaucous, with conspicuous membranaceous margins, the outer loose ; blades 1 to 

 9 inches long, f to 1| lines wide, usually longitudinally folded, glaucous, scabrous 

 on the midrib margins and upper surface, apex abruptly acute or mucronate ; lig- 

 ule about i line long, membranaceous, minutely ciliate at the apex. Leaves of the 

 stem 2 to 4, similar to those of the root ; sheaths not contiguous, upper more or 

 less inflated ; blade of the uppermost leaf often very small. 



Inflorescence a more or less long-peduncled cluster of sessi] e spikes. Spikes 7 to 

 16, 1 to 2 inches long; spikelets borne in 2 rows along one side of the slender, 

 scabrous rachis, inserted in each row at intervals of about f line. 



Spikelet slightly less than 1 line long, of the form of an equilateral triangle. 



Glumes 4 ; first and second oblong-lanceolate, hyaline, 1-nerved, nerve green 

 and usually glabrous, apex acute or obtuse, first about i line long, second | to f 

 line ; third (flowering) glume compressed, 3-nerved, short-ciliate on the keel and 

 intramarginal nerves, otherwise glabrous, bearing below the apex a minute scab- 

 rous awn i line long, each half of the glume oval, bluntly acute at either end; 

 fourth (sterile) glume compressed, glabrous, awned similarly to the third, 5- to 7- 

 nerved, the lateral nerves distant from the middle nerve, each half of the glume 

 wedge-truncate, as broad as long, apex and free margin involute. Rudiment of a 

 fifth glume usually present. 



.Mower single, hermaphrodite. Palet oval, 2-nerved, apex broadly notched, 

 nerves ciliate, intramarginal, the narrow margins inflexed. Stamens 3 ; anthers 

 ovate, sagittate, minute. Stigmas short, cylindrical. 



Grain oblong, acute at both ends, loosely inclosed in its glume and palet, upper 

 portion of the spikelet falling away together, rachilla disarticulating above the 

 second glume. 



Plate XXXI ; a and 6, spikelet, the parts opened and the rachilla broken at the 

 point of disarticulation. The flowering glume (to the left in b) should be ciliate on 

 the back and the awn scabrous. The sterile glume (on the right in 6) should be 

 similarly awned, and the palet should be ciliate on the margins. 



