424 



GRAMINE.E. 



Panicum. 



3. Panicum filiforme, Linn. (Plate CXLVII.) Slender Crab-grass. 



Culm filiform, erect ; lower sheaths very hairy ; spikes 2-4, filiform, alternate and ap- 

 proximate, rather loosely flowered ; spikelets in twos and threes, all of them pedicellate, 

 elliptical-oblong, acute, pubescent ; lower glume wanting ; perfect flower as long as the lower 

 glume. — Linn. sp. 1. p. 57 ; Trin. diss. 2. p. 54, ic. 13. t. 148, and Pun. gram. I. c. p. 204. 

 Digitaria filiformis, Beauv.; Mnhl. gram. p. 131 ; Ell. sk. 1. p. 132 ; Torr. fl. 1. p. 155 ; 

 Beck, hot. p. 398 ; Darlingt. fl. Cest. p. 44. Paspalum filiforme, " Fliigge, mon. Pasp. 

 p. 145 ; " Kunth, enum. 1. p. 46, excl. syn. Swartz. 



Annual. Culm 1-2 feet high, extremely slender, smooth. Leaves 1-2 inches long, 

 smooth underneath, sometimes a little hairy above : upper sheaths smooth ; the lower ones 

 sparsely clothed with slender spreading hairs. Spikes mostly 2 or 3, sometimes 4, an inch or 

 two in length ; the rachis very narrow and flexuous. Pedicels divided to the base, bearing 

 2-3 spikelets, which are about three fourths of a line long. No trace of an inferior glume; 

 the superior a little shorter than the palea of the neuter flower. Perfect flower with the palea? 

 finely striate, nearly black at maturity. 



Dry sandy soils : frequent. Fl. August. In the absence of the outer glume, this plant 

 resembles Paspalum ; but on account of its habit, I have retained it in the subgenus Digitaria. 



** Echinochloa, Beauv. Lower flower of Ike spiMels staminale or neuter. Glumes (unequal) and lower palea of the 

 slaminalc flower awned or mucronate. — Spikelets disposed in spikes, which arc usually paniculate. 



4. Panicum Crus-galli, Linn. Barnyard Grass. 



Spikes alternate and in pairs, simple or compound, the spikelets imbricated ; glumes and 

 lower palea of the neuter flower hispid, awned or mucronate ; rachis bristly ; sheaths smooth. 

 — Linn. sp. 1. p 156 ; Engl. hot. I. 876 ; Michx. fl. 1. p. 46 ; Bigel. fl. Bost. p. 40 ; 

 Pursh, fl. 1. p. 66 ; Muhl. gram. p. 105 ; Ell. sk. 1. p. 114 ; Trin. diss. 2. p. 135; Torr. 

 fl. 1. p. 140; Darlingt. fl. Cest. p. 49. Echinochloa, Beauv. Agrost. p. 53. Oplismenus 

 Crus-galli, Kunth, enum. 1. p. 143 ; Hook. fl. Bor.-Am. 2. p. 236. 



var. hispidum : sheaths hispid ; awns very long. — Ell. sk. I. p. 114. P. hispidum, Muhl. 

 gram. p. 107 ; Torr. fl. 1. p. 141. P. Walteri, Pursh, fl. 1. p. 66 (not of Muhl. and Ell.). 

 P. muriatum, Michx. fl. 1. p. 47? Oplismenus muricatus, Kunth, I. c. ; Hook. I. c. 



Annual. Culm 2-4 feet high, stout, erect or somewhat procumbent. Leaves half an inch 

 or more in breadth. Panicle dense, pyramidal ; the spikelets crowded in dense spike-form 

 racemes. Glumes acute ; the awn variable in length, and sometimes wanting. Outer palea 

 of the neuter flower usually awned. Perfect flowers smooth and coriaceous. 



Wet places, and about barnyards : common ; the rough-sheathed variety along ditches near 

 the salt water. Fl. August - September. 



