554 GRAMINEJi. (GRASS FAMILY.) 



palea 5-nerved, rough-keeled, about as long as the awn, much longer than the 

 hairs at the base. — Swamps, North Carolina, and northward. Aug. and Sept. 

 — Culms 2° -3° high. Leaves somewhat glaucous. Panicle £° long, purplish. 



§ 2. AMMOPIIILA. — Glumes and pale<e somewhat coriaceous: panicle spike-like. 

 2. C. arenaria, Poth. Culms and elongated convolute leaves rigid ; pan- 

 icle long (5' -9'), cylindrical; lower palea 5-nerved, obscurely awncd, 3 times 

 as long as the hairs at the base. — Sandy sea-shore, North Carolina, and north- 

 ward. Aug. — Pootstock creeping. Culm 2° -3° high. Spikelets, like tho 

 whole plant, whitish, £' long. 



13. STIPA, L. Feather-grass. 



Perennial grasses, with convolute leaves, and loose panicles of 1 -flowered 

 spikelets, with very long awns. Glumes 2, membranaceous, nearly equal, awn- 

 less and persistent. Palea? coriaceous, involute, raised on an obconical bearded 

 stalk, the lower one with a twisted or contorted awn jointed with its apex. Sta- 

 mens 3. Grain terete, enclosed in the palea?. 



1. S. avenacea, L. Culms ( 1° - 2° high) clustered ; leaves narrowly linear, 

 rough, the lowest elongated ; awn pubescent, bent in the middle, many times 

 longer than the dark-brown palea. — Dry soil, Florida, and northward. April. 



14. STREPTACHNE, P. Brown. 



Grasses with the habit of Aristida. Spikelet 1 -flowered; flower stalked. 

 Glumes 2, loose, awnlcss. Paleoe 2 ; the exterior cylindrical-involute. Awn 

 terminal, simple, jointless, twisted below ; the inner palea included, awnlcss. 

 Stamens 3. Styles 2. Stigmas plumose. 



1. S. ? Floridana, n. sp. Culms (2° high) simple, slender, erect; leaves 

 long, filiform, convolute, smooth; sheaths hairy at the throat; panicle (1° long) 

 narrow, erect, the rough branches by pairs, scattered ; spikelets short-stalked ; 

 glumes equal, linear, purple, 1 -nerved, the lower one awn-pointed, hispid-serru- 

 late on the back, the upper smooth, truncated, mueronate-awned ; palea: raised 

 on a slender bearded stalk, smooth, shorter than the glumes ; the lower one lin- 

 ear-subulate, gradually tapering into the long compressed curved awn, convo- 

 lute, and enclosing the capillary inner one. — South Florida, Dr. Blodyett. 



15. ARISTIDA, L. Wire-Grabs. 



Dry and harsh perennial grasses, growing in barren soil, with narrow leaves, 

 racemose or spiked-panicled 1 -flowered spikelets nearly as in Stipa, hut the lower 

 palea ending in a triple awn, which is continuous with its apex (except in 

 No. 9). Upper palea minute. Grain linear. 



* Glumes unequal, the upper one shorter. 

 1. % lanata, Poir. Culms stout (2°-3° high), simple; leaves flat, rough 

 on thcjppcr side, the sheaths, like the axils of the loose panicle, woolly; lower 

 palea (*^ long) as long as the upper glume and lateral awns, and one half as 



