GR AMINES (GRASS FAMILY.) 551 



divaricate, the lateral a little shorter than the mkldle one. Virginia to Illinois, 

 and south westward. Resembles small forms of the next. 



* * Aivns unittd below into one, jointed with the apex of the palea: root annual. 



7. A. tiibercilldsa, Nutt. Culm branched below (6' -18' high), tumid 

 at the joints ; panicles rigid, loose ; the branches in pairs, one of them shori and 

 about 2-flowered, the other elongated and several-flowered; glumes (!' long, in- 

 cluding their slender-awned tips) longer than the palea ; which is tipped with 

 the common stalk (about its own length) of the 3 equal divergently-bent awns 

 (1|' -2' long) twisting together at the base. Sandy soil, E. Massachusetts to 

 New Jersey ; also Wisconsin, Illinois, and southward. 



16. SPAR TIN A, Schrebcr. CORD or MARSH GRASS. 



Spikelets 1 -flowered, without a rudiment, very much flattened laterally, spiked 

 in 2 ranks on the outer side of a triangular rhachis. Glumes strongly com- 

 pressed-keeled, acute, or bristle-pointed, mostly rough-bristly on the keel ; the 

 upper one much larger and exceeding the pointless and awnless paleas, of which 

 the upper is longest. Squamulce none. Stamens 3. Styles long, more or less 

 united. Perennials, with simple and rigid reed-like culms, from extensively 

 creeping scaly rootstocks, racemed spikes, very smooth sheaths, and long and 

 tough leaves (whence the name, from (TTrapTivrj, a cord, such as was made from 

 the bark of the Spartium, or Broom). 



.*- Spikelets compactly imbricated, rough-hispid on the keels: spikes more or less pedurtr- 

 cled: culm and leaves rigid. 



1. S. cynosuroides, Willd. (FRESH-WATER CORD-GRASS.) Culm 

 rather slender (2 -6 high) ; leaves narrow (2 -4 long, ^' or less wide below), 

 tapering to a very slender point, keeled, flat, but quickly involute in drying, 

 smooth except the margins ; spikes 5-14, scattered, spreading ; rhachis rough on 

 the margins ; glumes awn-pointed, especially the upper, the lower equalling the lower 

 palea, whose strong rough-hispid midrib abruptly terminates below the membra- 

 nous apex. (Trachynotia cynosuroides, Michx. Limnetis, Pers.) Banks of 

 rivers and lakes through the interior, chiefly northward. Aug. Spikes 2' -3' 

 long, straw-color. Glumes strongly serrulate-hispid on the keel ; the awn of the 

 upper one about \' long. Paleae somewhat unequal. Certainly distinct from 

 the next, to which, in strictness, the Linnaean name belongs. 



2. S. polystacliya, Willd., Muhl. (SALT EEED-GRASS.) Culm taH 

 and stout (4 - 9 high, often 1' in diameter near the base) ; leaves broad (Q to I'), 

 roughish underneath, as well as the margins ; spikes 20-50, forming a dense obfang 

 raceme (purplish) ; glumes barely mucronate, the lower half the length of t/ie equal 

 paleie, of which the rough-hispid midrib of the lower one reaches to the apex. 

 (Trachynotia polystacliya, Michx. Dactylis cynosuroides, L.I in part, excl, 

 var.) Salt or brackish marshes, within tide -water, especially southward. 



3. S. jtiaicea, Willd. (llusn SALT-GRASS.) Culms low (1~2 high; 

 and slender; leaves nairoiv and rush-like, strongly involute, very smooth ; spikes 1-5, 

 on vety short peduncles; the rhachis smooth ; glumes acute, the lower scarcely J 

 the length of the upper, not half the length of the lower palea. (Dactylxs pa- 



