GRAMlNEiE. (gRASS FAMILY.) 555 



long as the middle one. — Dry pine barrens, Florida to North Carolina. July 

 and Aug. — Lower palea spotted with ]iurple. 



2. A. purpurascens, Poir. Culms (\^°-2° high) slender, sparingly 

 branched ; sheaths smooth ; glumes sometimes nearly equal, purple ; lower 

 palea (3" long) ^-J as long as the nearly equal awns. — Dry soil, Florida, 

 and northward. Aug. — Panicle slender, 1° long, with the branches appressed. 



* * Glumes equal, or the tipper one longer. 



3. A. gracilis, Ell. Culms much branched at the base, very slender ; 

 leaves flat ; panicle very narrow, with distant appressed branches ; middle awn 

 rather longer than the rough and spotted lower palea, the lateral ones much 

 shorter ; glumes nearly equal. — Dry gravelly soil, Florida to North Carolina. 

 Aug. — Culms (with the panicle) 6' -12' high. Spikelets purple. 



4. A. virgata, Trin. Culms (2° -3° high) branched near the base; leaves 

 flat, rigid; panicles (1° long) loose; glumes nearly equal; middle awn spread- 

 ing, twice as long as the erect lateral ones, and four times the length of the short 

 (2" long) lower palea. — Dry soil, Florida to North Carolina. 



Var? palustris. Every way larger (3° -.5° high), with the panicle 1|^°- 

 2^° long, and the straight awns nearly equal. — Margins of pine-barren ponds, 

 West Florida. Aug. and Sept. 



5. A. Stricta, Michx. Culms (2° -3° high) tufted, simple, straight ; leaves 

 chiefly radical, filiform, involute, rigid, hairy at the base; panicle (1° long) 

 spiked ; lateral awns as long as the lower palea, the middle one one tliird 

 longer. — Dry sandy ridges in the pine barrens, very common. June and July. 



6. A. dichotoma, Michx. Culms low, fork-branched ; leaves Aliform, 

 erect; panicle (2'- 3' long) spiked; glumes purple, longer than the paleae and 

 the very short and erect lateral awns, the middle awn shorter than the paleae, 

 spreading. — Dry soil in the upper districts. Aug. and Sept. — Culms 6'- 12' 

 high. 



7. A. Spieiformis, Ell. Culms simple, rigid, erect (l°-li° high); 

 leaves rigid, erect, convolute, smooth ; panicle spiked ; glumes much shorter 

 than the long (1') very slender paleae, the upper one twice as long as the 

 lower ; awns nearly equal, widely spreading, the middle one as long as the 

 paleas. — Low pine barrens, Florida to South Carolina. Aug. and Sept. — 

 Panicles 2' - 4' long, at length twisted. 



8. A. Oligantha, Michx. Culms (l°-2° high) branched, slender; leaves 

 filiform, convolute ; spikelets scattered, single or by pairs, in a simple terminal 

 raceme ; glumes nearly equal, longer than the pale» ; middle awn very long 

 (2'), rather longer than the lateral ones, and 2-3 times the length of the 

 palefE. — South Carolina or Georgia, Nultall. Sept. 



9. A. tuberculosa, Nutt. Culms rigid, branching (l°-li° high) ; leaves 

 flat ; glumes nearly equal, longer than the paleae, bristle-awned ; awns (2' long) 

 equal, jointed with the paleae, twisted below, then widely spreading, several times 

 longer than the palea. — Dry ridges, in the middle districts of Georgia. Sept 

 — Panicle simple. 



