142 



GRAMINEAE (GRASS FAMILY) 



Teeth of the lemma trianjrular, not aristate 



Teeth of the lemma aristate. 



Florets not over 5 mm. long 



Florets 7-S mm. long. 

 Spikelets nearh- sessile, in small crowded panicle, purple . . . 

 Spikelets in loose panicle, pale green. 

 Sheaths and blades villous ; lemma silky -hairy .... 



Sheaths and blades glabrous ; lemma pubescent on margins and base 



1. D. spicata. 



2. D. compressa. 



3. D. intermedia, 



4. Z>. sericea. 



5. D. epilis. 



1. D, spicata (L.) Beauv, Culms 2-7 dm. high terete ; sheaths and iiivohite 



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 



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



^ly^ l/\ lemmas 4-5 mm. long, sparsely clothed with stiff hairs, teeth 



"^ tHangulai\ the awn longer than the lemma. — Dry and sterile 



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



2. D. compressa Aust. Usually taller than the preceding : 

 culms flattened^ often decumbent at base ; leaves elongated, 

 2-3 mm. loide, 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 7)im. long, rather crowded in a raceme or 

 simple few-floioered 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 ; 

 axon 7-8 mm. long. — Mt. Albert, Gaspe Co., 

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

 Aug. 



4. D. sericea 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 

 than I the entire length of the lemma, awn 12-15 mm. long. — 

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



5. D. epilis Scribn. Very similar to the preceding, not so tall ; sheaths and 

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

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

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



126. D. spicata. 

 Panicle x l^. 

 Spikelet and floret 



Lemma x 2. 



127. D. sericea. 

 Lemma x 4. 



48. SPARTINA Schreb. Cord or Marsh Grass 



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 cri-eping 

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

 (nrapTLvri, a cord, such as was made from the bark of the Spartium or broom.) 



* Culms stout, usually over 1 m. high; leaves 1 cm. or more imde, flat or 



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. 



