438 
the branches in pairs, one of them short, and about two-flowered, the other 
elongated and several flowered; small tubercles in the axils; glumes bristle 
awned, longer than the palea, which is tipped with the common stalk of the 
three equal divergently bent awns, twisting together at the base. Annual; 
flowers in July and August; culms 6 to 18 inches high. Dry prairies; Illi¬ 
nois; pine barrens of the St. Croix river, Wisconsin.— Dr. C. C. Parry. 
TRIBE V. CHLORIDES. 
Spikelets usually several flowered, (rarely one-flowered,) with the up¬ 
per flowers imperfect, disposed in one-sided racemose or digitate spikes; 
glumes persistent, the upper one appearing as the outer one; rachis joint¬ 
less ; stamens 2 or 3. 
GENUS 16. SPARTINA. Schreber. 
[From spartine a cord, on account of the long tough leaves.] 
Spikelets one-flowered, very flat, closely imbricated in two rows on the 
outer side of a triangular rachis ; glumes unequal, acute, or bristle- 
pointed, serrulate on the keel, the upper one larger ; palea membranace¬ 
ous awnless, shorter than the upper glume ; stamens three. 
44. Spartina Cynosuroides. Willdenow. 
Syn. —Trachynotia cynosuroides, Michx. Limnetis cynosuroides, 
Perroon. Fresh water cord-grass. 
Culm rather slender; leaves long and narrow, tapering to a very slen¬ 
der point, keeled, flat, smooth except on the margins ; spikes five to ten, 
scattered, spreading; glumes awn pointed, the lower equaling the lower 
palea. Perennial; flowers in August; fruit ripe in September; culms 
2 to 4 feet high. 
River banks, and margin of lakes—common. Wisconsin, Illinois, In¬ 
diana, Ohio, Michigan and Minnesota. 
i 
GENUS 17. BOUTELOUA. Lagasca. 
[Probably named after some Spaniard.] 
Spikelets ciowded and closely sessile in a short spike on one side of a 
flattened lachis ; the spikes in a simple raceme; glumes keeled, the lower 
one shoiter , lower palea of the perfect flower three-nerved, three-tooth¬ 
ed at the apex; the upper palea two-nerved and two-toothed; the nerves 
