67 



Diplaohne, Beauv. 



Spikelets many-flowered, narrow, sessile or nearly so, and distant 

 on the long slender branches of the panicle, usually in two rows, 

 but not regular as in Leptochloa ; outer glumes keeled, acute, not 

 awued ; flowering glumes one to three nerved, with a thin or hyaline 

 shortly two-lobed apex, the keel produced into a short point or awn 

 between the lobes; palet thin, prominently two-nerved. 



1. D. biflora, Scrib. Arizona. 



2. D. dubia, Benth. (Leptochloa dubia, JVees.) Florida to Texas. 



3. D. fascicularis, Benth. (Leptochloa fascicularis, Gr.) New Eng- 



land to Arizona. 

 An annual grass of vigorous growth, 2 to 3 feet high, growing in 

 brackish marshes or wet ground near the sea-coast, and also far in- 

 land in the Mississippi Valley, Texas, Arizona, &c, in alkaline soil. 



4. J), imbricata, (Leptochloa, Thurb.) Arizona. 



5. D. rigida, (Leptochloa, Munro.) Florida to Texas. 



6. D. viscida, Scrib. Texas to Arizona. 



Tkiplasis, Beauv. 



Panicle simple and scanty, partly included in the leaf-sheath ; 

 spikelets remotely two to five flowered ; outer glumes much shorter 

 than the flowers, membranaceous, one-nerved ; flowering glumes two- 

 lobed or two-cleft, the midnerve extended into an awn between the 

 lobes, three-nerved, strongly fringed on the nerves ; palet shorter, 

 two-keeled, long ciliate on the keels. 



1. T. Americana, Beauv. (Uralepis cornuta, Mutt.) South. 



2. T. purpurea, Chap. (Uralepis purpurea, N~utt.) North and South. 



3. T. sparsiflora, Chap. Florida. 



Eremochlox, 8. Watson. 



Panicle short and contracted, simple, or nearly so ; spikelets fonr- 

 flowered, the two lower flowers neutral, the third flower perfect and 

 fertile, the uppermost reduced to a stipitate villous triple awn ; outer 

 glumes membranaceous, carinate, one-nerved, acute, glabrous, nearly 

 equal ; flowering glumes three-nerved, two-cleft to the middle, the 

 nerves strongly villous, extended into awns, of which the middle one 

 is longest; the lobes in the neutral flowers obtuse, in the perfect 



