GRAMINEJE. (GRASS FAMILY.) 619 



*+ ++ Upper glume shorter than the lower: perennials, simple-stemmed, 2° -4° high. 



6. A. purpur&SCens, Poir. Glabrous; leaves rather involute; flowers 

 in a (10'- IS') long spiked panicle; awns much longer than the flower, the middle 

 one about 1' long. (A. raeemosa, Muld. A. Geyeriana, Steud.) — Massachu- 

 setts to Michigan, Illinois, and southward: common. 



7. A. hinata, Poir. Tall and stout ; leaves tardily involute, rough on the 

 upper side, rigid; sheaths woolly ; panicle (l°-2° long) spike-like or more com- 

 pound and open; middle awn (1' long) longer than the flower. — Salisbury, 

 Maryland, W. M. Canby, and southward. 



* * Awns united below into one, jointed with the apex of the pal et : root annual. 



8. A. tubercul6sa, Nutt. Culm branched below (6'- 18' high), tumid 

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

 about 2-flowered, the other elongated and several-flowered; glumes (1'long, in- 

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

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

 (l£'-2' long) twisting together at the base. — Sandy soil, E. Massachusetts to 

 New Jersey ; also Wisconsin, Illinois, and southward. 



17. SPARTINA, Schreber. Cord or Marsh Grass. (PI. 9.) 



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

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

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

 much larger and exceeding the pointless and awnless palets, of which the upper 

 is longest. Squamulte 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 o-rraprivn, a cord, such as was made from the 

 bark of the Spartium or Broom.) 



* Spikelets compactly imbricated, very rough-hispid on the heels: spikes (2' -4' long) 

 more or less peduncled : culm and elongated leaves rigid. 



1. S. cynosuroides, Willd. (Fresh-water Cord-Grass.) Culm rather 

 slender (2° -6° high) ; leaves narrow (2° -4° long, J' or less wide below), taper- 

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

 except the margins; spikes 5-20, scattered, spreading; rhachis rough on the 

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

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

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

 rivers and lakes, especially northward. Aug. — Glumes strongly serrulate-hispid 

 on the keel ; the awn of the upper one about Y long. Palets somewhat unequal. 

 — Certainly distinct from the next, to which, in strictness, the Linnosan name 

 belongs. 



2. S. polystachya, Willd., Muhl. (Salt Reed-Grass.) Culm tall and 

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

 wughish underneath, as well as the margins; spikes 20-50, forming a dense oblong 

 raceme (purplish) ; glumes barely mucronate, the lower half' the length of the equal 

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



