142 



GEAMINEAB (GRASS FAMILY) 



Teeth of the lemma triangular, not aristate 1. B. spicata. 



Teeth of the lemma aristate. 



Florets not over 5 mm. long 2. 2). coinpresm. 



Florets 7-8 mm. long. 

 Spikelets nearly sessile, in small crowded panicle, purple . , . , S. D. intermedia. 

 Spikelets in loose panicle, pale green. 



Sheaths and blades villous ; lemma silky -hairy i. 2). sericea. 



Sheaths and blades glabrous ; lemtna pubescent on margins and base 



only . ... 5. Z>. epilis, 



1. D. spickta (L.) Beauv. Culms 2-7 dm. high terete. ; sheaths and involute 

 blades glabrous or sparsely pilose, the numerous basal leaves often curled, those 

 of the culm erect ; panicle few-flowered, the few short branches 

 erect or ascending, often reduced to . a raceme ; spikelets 

 10-12 mm. long, on short stiff pedicels ; glumes acuminate : 

 lemmas 4-5 mm. long, sparsely clothed with stiff hairs, teeth 

 triangular, the awn longer than the lemma. — Dry and sterile 

 or rooky soil. June-Aug. Fig. 126. 



2. D. compr^ssa Aust. Usually taller than the preceding : 

 culms flattened, often decumbent at base ; leaves elongated, 

 2-3 mm. wide, flat or involute on the margins only ; panicle 

 more open ; teeth of the lemma aristate, at least 

 2 mm. long. — Dry woods, Me. to N. Y., and 

 southw. 



3. D. intermedia Vasey. Culms 1-4 dm. high, 

 with numerous mostly involute basal leaves ; 

 culm-leaves 5-15 cm. long, involute ; spikelets 

 15 mm. long, rather crowded in a raceme or 

 simple few-flowered panicle ; glumes broad, acu- 

 minate, purplish, with pale scarious margins; 

 lemma 7-8 mm. long, glabrous except at the base 

 and margins below the middle, the teeth aristate ; 

 awn 7-8 mm. long. — Mt. Albert, Gasp6 Co., 

 Que. ; n. Mich. (Parwell), and westw. July, 

 Aug. 



t./^ 4. D. serloea Nutt. Culms 5-9 dm. high ; sheaths and blades 



villous, at least the lower ones ; basal blades elongated, mostly 



involute, those of culms flat or involute ; panicle 6-10 cm. long, 



rarely longer, rather loose, the branches ascending or spreading ; 



spikelets about 1.5 mm. long; glumes narrow, acuminate, pale; 



lemma densely clothed with long silky hairs, the aristate teeth more j.^^ j, s^jjcea 



than I the entire length of the lemma, awyi 12-15 mm. long. — ^ Lemma x 4 



Sandy soil, Mass. to Pa., and southw. Fig. 127. ^ 



5. D. fipilis Soribn. Very similar to the preceding, not so tall ; sheaths and 

 blades glabrous ; panicle smaller ; lemma glabrous, except at the base and on the 

 margins below the middle. (D. glabra Nash, not Philippi.) — Sandy soil, N. J., 

 and southw. j rare. May. — Possibly only a variety of the preceding. 



126. D. spicata. 

 Panicle x ^. 

 Spikelet and floret 



Lemma x 2. 



48. SPARTiNA Schreb. Cokd or Marsh Gkass 



Spikelets 1-flowered, flattened laterally, sessile and closely imbricated in 2 

 rows along one side of a continuous rhachis, forming unilateral spikes which are 

 scattered along a common axis ; glumes unequal, keeled, acute or bristle- 

 pointed, the second usually exceeding the obtuse thinner 1-nerved lemma ; 

 palea equaling or exceeding the lemma. — Coarse perennials with strong creeping 

 rootstocks, rigid simple culms, and long tough leaves. (Whence the name, from 

 unaprlvni, a cord, such as was made from the bark of the Spartinm or broom.) 



* Culms stout, usually over 1 m. high; leaves 1 cm. or more wide, flat i li- 

 nearly so when fresh. 



1. S. Michauxiana Hitchc. (Slough Grass.) Culms 1-2 m. high ; 

 leaves 6-12 dm. long, 15 mm. wide or less, tapering to a very slender point, 



