1836.] Description of some Gramineous Plants. 571 



Ovarium ovato-oblongum, glabrum. Styli 2. Stigmata plumosa, 

 divisionibus ramosis, ratione stylorum longa. 



Caryopsis .... 



Legimus in aquosis Jumalpore, in plagis inundatis, Jheels verna- 

 cule dictis, Sylhet confinibus ; in collibus Khasiensibus prope Nunkloiv ; 

 et nuperius in regione Assamica alta ; annis 1835-36. 



With regard to this grass, we have Mr. Brown's authority (Prodr. 

 Fl. Nov. Holl. ed. Nees 1. p. 67, sub LeptaspideJ for its being 

 totally distinct from Pharus, to which it was originally referred 

 by Retzius. Mr. Brown likewise points out (loc. cit.) that this and 

 the succeeding, if not retainable in Zizania, will constitute a distinct 

 genus. It will be seen that I have ventured to go farther, and I am 

 only deterred from characterizing this as itself distinct, by the diffi- 

 culty I find in distinguishing it from Leersia, with which genus I am 

 only acquainted through M. Kunth's Agrostographia. Its obvious 

 affinity is with Oryza, from the awnlets varieties of which it only dif- 

 fers in the total absence of glumes ; the presence of the membranous 

 cup terminating the pedicel in Oryza proving, that it is not to be consi- 

 dered as a modification of these envelopes. 



POTAMOCHLOA. Griff. 



Syst. Linn. Hexandria Digynia. Order, Nat. Graminete, J uss. 



Spiculae uniflorae. Glumae nulla?. Paleae 2 membranaceo-chartacese, 

 carinatae, apertae, exteriore in aristam producta. Lodiculse 2. Stamina 

 6. Styli 2. Stigmata plumosa. 



Caryopsis 



Gramen fluitans ope vaginarum cellulosarum, dense caespitosum. 

 Folia lata ; ligula obsoleta. Panicula eftusa erecta ; pedicelli infra 

 medium constricti. 



Potamochloa Retzii. Griff. 



Zizania? aristata. Kunth, Agr. p. 10. 



Leersia aristata. Roxb. Flor. hid. 2. p. 207. 



Pharus aristatus. Retz. Obs. 5, 23, ex Kunth. 



Hab. In aquis stagnantibus prope Jumalpore, et copiosissime 

 in inundatis, Jheels dictis, Sylhet confinibus. Legimus florentem 

 Septembre, 1835. 



Culmi emersi vix pedales, glabri. Immersi longissimi, hinc illinc 

 radiculas capillaceo-divisas emittentes. 



Vaginae immersaa vel semi-immersae quam maxime cellulosae, in- 

 crassatae et quasi inflatae ; emersae longiores cylindraceae, minus 

 cellulosae. 



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