GRAMINACE^E. 453 



** Flowers in spikes. 



2. A. scoparius Mich. : spikes simple, lateral and terminal, pedunculate, 

 in pairs ; lower flower neutral, awned ; glumes of the perfect flower smooth ; 

 awn twisted. A. purpurascens Willd. 



Old fields and road sides. N. Y. and Mass, to Car. W. to Ohio. Aug. %. 

 Culm about 3 feet high, with lateral scattered branches. Leaves flat, some- 

 what hairy. Spikes on a flexuous rachis, often purple. 



Purple Bear-grass. Brown-grass. 



3. A. furcatus Muhl.: spikes digitate, generally in threes or fours; lower 

 flower staminate, awnless ; awn of the perfect flower somewhat contorted. 



Rocky grounds. N. Y. and Mass, to Car. W. to Ark. Aug., Sept. %. 

 Culm 34 feet high, simple or somewhat branching. Leaves flat; the lower 

 very long. Spikes about 3 inches long, 3 5 or more at the summit of the culm. 



Forked Beard-grass. 



4. A. macrourus Mich. : spikes fasciculate, in dense lateral and terminal 

 fastigiate panicles ; lower flower a mere rudiment without valves ; perfect 

 flower monandrous, the awn straight. 



Swamps, especially near salt water. N. Y. and Mass, to Flor. Sept., Oct. 

 1\.. Culm 3 feet high, much branched towards the top. Leaves roughish ; the 

 lower long. Spikes very numerous, in large clustered panicles, partly concealed 

 in the boat-like sheaths. Many-spiked Beard-grass. 



5. A. Virginicus Linn. : culm somewhat compressed ; sheaths smooth ; 

 spikes short, 2 3 from each sheath, in slender fascicles, lateral and termi- 

 nal ; lower flower a mere pedicel without glumes ; perfect flower monan- 

 drous, the awn straight. A. dissitiflorum Mich. 



Dry swamps. N. Y. and Mass, to Flor. Sept. 'Zj-. Culms about 3 feet high, 

 somewhat cespitose, with short branches above. Leaves a foot or more in 

 length, the lower hairy on the upper surface. Spikes partly concealed in sheaths. 



Virginian Beard-grass. 



