GRAMINE.E. (GRASS FAMILY.) 583 



64. ANDROPOOON, L. BEARD-GRASS. 



Spikelets in pairs upon each joint of the slender rhachis, spiked or raceraed ; 

 one of them pedicellcd and sterile, often a mere vestige : the other sessile, with 

 the lower flower neutral and of a single palea ; the upper perfect and fertile, of 

 2 thin and hyaline palcse shorter than the herbaceous or chartaceous glumes, the 

 lower awned from the tip. Stamens 1-3. Grain free. Coarse and mostly 

 rigid perennial Grasses, with lateral or terminal spikes commonly clustered or 

 digitate ; the rhachis hairy or plumose-bearded, and often the sterile or stami- 

 natc flowers also (whence the name, composed of dvfjp, ai/Spos, man, and Trtoywv, 

 beard). 



* Stsrite spikekt staminote (stamens 3), aicnless: spikes digitate. 



1. A. furcatll, Muhl. Culms (4 high) and leaves nearly smooth, 

 bearing 3-5 straight and rather rigid hairy spikes together at the naked summit 

 (or fewer on lateral branches) ; spikelets approximated, roughish-downy ; awn 

 bent. Sterile soil ; common. Sept./ 7 



* * Sterile spikclet neutral, reduced to "a small pointed glume^raised on a long bearded 

 pedicel ; the fertile 2 - 3-androus, bearing a slender mostly bent or twisted awn : culms 

 paniculate-branched. 



2. A. scoparilis, Michx. Culms slender (2 - 4 high), with many pa- 

 niculate branches ; the lower sheaths and the narrow leaves hairy ; spikes mostly 

 single, terminating the short branches, pedunclcd, very loose, slender (2' long, often 

 purple), sparsely silky icith dull white hairs; the zigzag rhachis hairy along the 

 edges ; pairs of spikelets rather distant. Sterile or open sandy soil ; common. 

 July - Sept. 



3. A. argenteilS, Ell. Culms rather slender (about 3 high) ; spikes in 

 pairs, on a peduncle exceeding the sheaths, dense, very silky with long white hair 

 (1^' 2' long) ; rudimentary flower much shorter than the hairs of its pedicel. 

 Sterile soil, Virginia, Illinois? and southward. Sept., Oct. Spikes much 

 denser, and the flowers larger and more silky, than in the next ; which it con- 

 siderably resembles. 



* * * Sterile spikelet aborth-e, reduced to a mere awn-like plumose pedicel, or bearing 

 distinct rudiment of a flower: the fertile l-androus, and bearing a straight slender 

 awn : s/iikes clustered, lateral and terminal, partly enclosed in the flattened bract' 

 like sheaths; the slender rhachis, $ - c. clothed with copioui very hug and silki/ 

 (white) hairs. 



4. A. VirgilliCUS, L. Culm flattish below, slender, sparingly short- 

 branched above (3 high) ; sheaths smooth ; spikes 2 or 3 together in distant oppressed 

 clusters, weak and soft (!' long). Sandy soil ; Massachusetts to Illinois, and 

 southward. Sept. 



5. A. imicroftrilS, Michx. Culm stout (2-3 high), bushy-branched at 

 the summit, loaded with numerous spikes forming dense leafi/ dusters; sheaths 

 rough, the upper hairy. Low grounds, New York to Virginia, near the coast, 

 nnd southward. Sept., Oct. 



SO 



