682 GRAMINE^E. (GRASS FAMILY) 



less downy, enclosing 2 or 3 spikelets. (I) Sandy soil, on the coast, and along 

 the Great Lakes; ascending the larger rivers for some distance. Aug. A 

 vile weed. 



62. TRIPSACUM, L. GAMA-GRASS. ' SESAME-GRASS. 



Spikelets monoecious, in jointed spikes, which are starninate above and fertile 

 below. Staminate spikelets 2, sessile at each triangular joint of the narrow 

 rliachis, forming a 1-sided and 2-rankcd spike longer than the joints, both alike, 

 *2-flowered : glumes coriaceous, the lower one (outer) nerved, the inner one boat- 

 shaped : paleae very thin and mcmbranaceous, awnless : anthers (turning orange 

 or reddish-brown) opening by 2 pores at the apex. Pistillate spikelets single 

 and deeply imbedded in each oblong joint of the cartilaginous thickened rhachis, 

 occupying a boat-shaped recess which is closed by the polished and cartilagi- 

 nous ovate outer glume ; the inner glume much thinner, pointed, 2-flowered ; 

 the lower flower neutral ; the paleae very thin and scarious, crowded together, 

 pointless. Styles united : stigmas very long (purple), hispid. Grain ovoid, 

 free. Culms stout laid tall, solid, from very thick creeping rootstocks. Leaves 

 broad and flat. Spikes axillary and terminal, separating spontaneously into 

 joints at maturity. (Name from Tpi/3&>, to rub, perhaps in allusion to the 

 polished fertile spike.) 



1. T. dactyloides, L. Spikes (4' -8' long) 2-3 together at the sum- 

 mit (when their contiguous sides are more or less flattened), and also solitary 

 from some of the upper sheaths (when the fertile part is cylindrical); some- 

 times, var. McmosTXciiYOM, the terminal spike also solitary. Moist soil, Con- 

 necticut to Pennsylvania, near the coast, thence west to Illinois, and southward. 

 Aug. Culm 4 - 7 high : the leaves like those of Indian Corn. This is one 

 of our largest and most remarkable Grasses. It is sonjetimes used for fodder at 

 the South, where better is not to be had. 



63. ERIANTIIUS, MSchx. WOOLLY BEARD-GRASS. 



Spikelets spiked in pairs upon each joint of the slender rhachis ; one of them 

 essile, the other pedicelled ; otherwise both aiike ; with the lower flower neu- 

 tral, of one membranaceous palea; the upper perfect, of 2 hyaline puleae, which 

 are thinner and shorter than the nearly equal membrannceous glumes, the lower 

 nwned from the tip. Stamens 1-3. Grain free. Tall and stout reed-like 

 Grasses, with the spikes crowded in a panicle, and clothed with long silky hairs, 

 especially in a tuft around the base of each spikelet (whence the name, from 

 fpiov, wool, and av6os, flower). 



\. E. alopccuroides, Ell. Culm (4-6 high) woolly-bcankd at the 

 joints; panicle contracted; the silky hairs longer than the spikelets, shorter than the 

 straight awn ; or at length contorted ; stamens 2. 1[ Wet pine barrens, New 

 Jersey, Illinois, and southward : rare. Sept., Oct. 



2. E. bretfibarbis, Michx. Culm (2 -5 high), somewhat bearded at 

 the upper joints ; panicle, rather open ; silky hairs shorter than the spikelets. 1| 



-Low grounds, Virginia and southward. 



