554 GRAMINE^E. (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. AMMOPHIL A. Glumes and pale.ce. somewhat coriaceous : panicle spike-like. 

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

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

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

 ward. Aug. Rootstock creeping. Culm 2 -3 high. Spikelets, like the 

 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. Paleae 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 paleae. 



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, R. Brown. 



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

 Glumes 2, loose, awnless. Palese 2 ; the exterior cylindrical-involute. Awn 

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

 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, mucronate-awned ; paleoe raised 

 on a slender bea/ded stalk, smooth, shorter than the glumes ; the lower one lin- 

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

 Jnte, and enclosing the capillary inner one. South Florida, Dr. Blodgett. 



15. ARISTIDA, L. WIRE-GRASS. 



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

 racemose or spiked-panicled 1 -flowered spikelets nearly as in Stipa, but 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. A. lanata, Poir. Culms stout (2-3 high), simple; leaves flat, rough 

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

 palea (4" long) as long as the upper glume and lateral awns, and one half as 



