No. 42. 

 DIPLACHNE IMBRICATA (Thurb.)Scrib. (LeptocMoa imbricata Tkurh.) 



Plant annual or short-lived perennial from "bulbous base, somewhat glaucous, 

 purplish on the sheaths and with dark green panicle. 



Culms tufted, erect, geniculate, branching, hollow, terete, smooth or minutely 

 scabrid near base of panicle, 1 to 2 feet tall. 



Leaves; radical and of radical shoots, numerous, with smooth, tapering, com- 

 pressed sheaths and narrow, slender pointed, folded or involute, hispid blades, 4 

 to 8 inches long ; of culm 3 or 4 ; sheaths striate, slightly roughened on upper part, 

 open above, nearly equaling internode ; blade like that of radical leaves but usu- 

 ally shorter ; ligule membranaceous, ovate, acute, entire, wider than the blade, 

 decurrent. 



Inflorescence a rather close, narrowly-oblong panicle, 4 to 6 inches long, of 

 numerous linear branches ; rachis angular, hispid ; branches hispid, slender, 

 mostly alternate, slightly spreading, li- to 2 inches long, bearing on the lower side 

 12 to 16 nearly sessile, appressed, and imbricate spikelets. 



Spikelets linear-oblong, 7- to 10-flowered, 2| to 3 lines long less than 1 line 

 wide ; internodes of glabrous rachilla articulate, i line long ; first glume ovate, 

 acute, carinate, ciliate, hispid on back, 1-nerved, f line long ; second glume ellip- 

 tic-oblong, obtuse, often slightly mucronulate, 1 to li lines long ; floral glume 

 oblong, truncate, with two short blunt teeth at the summit, the mid-nerve termin- 

 ating in a short mucro, membranaceous, pubescent on the lower half of the lateral 

 nerves, 1 line long ; palet lance-oblong, with rounded ciliate apex, two prominent 

 pubescent nerves and narrow infolded hyaline margin, 1 line long. 



Grain light-brown, obovate. falling with flower but easily separated. 



Plate XLII ; a, spikelet ; b, empty glumes ; c, floral glumes, dorsal and side 

 view ; d, palet. 



Texas, New Mexico, Arizona, and southern California. 



