138 GRAMINEAE (GRASS FAMILY) 



41. SPHENOPHOLIS Scribn. 



Spikelets 2-3-flowered, the pedicels jointed just below the glumes ; rhachilla 

 prolonged behind the upper palea in a slender pedicel, articulated between the 

 florets, the glumes and lower floret with joint of pedicel tardily falling together ; 

 glumes subequal, exceeded by the uppermost floret, the first narrow, the second 

 much broader, usually obovate, becoming subcoriaceous in fruit, 3-nerved ; 

 lemma chartaceous, nerves obscure, awnless or awned below the summit, awn 

 usually straight or divergent ; palea hyaline, narrowed toward the base ; grain 

 inclosed within the rigid lemma, free. — Slender perennials with usually flat 

 leaves and narrow terminal panicles. (Name from (rcpriv, a wedge, and 0oXts, a 

 scale, referring to the broadly obovate or wedge-shaped second glume. ) Eatonia 

 Eudlicher and later authors, not Raf. 



Spikelets awnless or with the second floret short-awned ; glumes dissimilar, the 

 first linear, second obovate, becoming chartaceous. 

 Panicle narrow, densely flowered ; second glume as broad as long, subcucullate 



in fruit 1. S. oMusata. 



Panicle lax, branches more or less spreading, at least in flower. 

 Glumes subequal, second broadly obovate, obtuse ; florets obtuse, the second 



very scabrous e 2. /S". nitida. 



Glumes unequal, first shorter than the narrowly obovate second one ; florets 



mostly acute, glabrous 3. S.pallens. 



Spikelets awned ; glumes similar. 



Lower floret usually awnless . 4. S. palustris. 



Both florets awned ... {4) S. palustris, v.flexuosa. 



1. S. obtusata (Michx.) Scribn. Culms slender to rather stout, 3-10 dm. 

 high ; sheaths pubescent to nearly glabrous ; leaves 4-15 cm. long, glabrous ; panicle 



6-18 cm. long, often glomerate; spikelets 2.5-3 mm. long; 



glumes subequal, the second subcucullate, the broad chartaceous 



margins smooth and shining ; lemmas similar or the second a 



little scabrous. — Dry soil, Ct. to Fla., westw. to Mo. and Tex. 



June, July. Fig. 116. Var. pubescens (Scribn. & Merr.) Scribn. 



Sheaths and sometimes culms and leaves pubescent. — Ct. to 

 116 S obtusata ^^'^^^- ^"^ southw. Var. lobXta (Trin.) Scribn. Sheaths and 

 Spikelet x^3. ^ leaves scabrous, not pubescent; panicle cylindrical, sometimes 



interrupted below ; spikelets densely crowded on the short ax>pressed 

 branches. — Dry soil, and prairies, Me. to Fla., westw. throughout the U. S. ; 

 the commoner form in the North. 



2. S. nitida (Spreng.) Scribn. Culms slender, 3-6 dm. high; sheaths pubes- 

 cent; leaves 3-6 cm. long, 2-5 inm. icide, pubescent; panicle 5-20 cm. long, 

 loosely flowered, widely spreading in flower, finally erect ; spikelets 3 mm. long, 

 cuneiform ; glumes subequal, the broad second glume rounded or abruptly apic- 

 ulate ; lemmas oblong, obtuse, rarely short-awned just below the apex, second 

 lemma scabrous especially near the tip and keel. {Eatonia Dudleyi Vasey.) — 

 Woods, Vt. to Mich., and southw. May, June. Var. glabra (Nash) Scribn. 

 Sheaths and leaves glabrous. — Va., and southw. 



3. S. pallens (Spreng.) Scribn. Culms 3-10 dm. high, usually slender; 

 sheaths usually glabrous, sometimes pubescent ; leaves 5-20 cm. long, 4.6 mm, 

 xcide, scabrous on the nerves, sometimes sparsely pilose above ; 

 panicles lax, nodding, 8-20 cm. long ; spikelets 3-4 mm. long, 

 oblong-lanceolate; glumes unequal, scabrous on the keels, the 

 first linear, ^| as long as the broadly oblanceolate usually acute 

 second glume; lemmas lanceolate, acute, glabrous except on the 

 keel near the apex, the second projecting beyond the second ^^^ g ^ugjjg 

 glume, sometimes awned below the apex. {Eatonia pennsylvanica gpikeietxS 

 Gray.) — Me. to N. C, w. to Wise, Kan., and Tex, — In the 

 Mississippi Valley this species occurs on prairies, and has a denser panicle ; in 

 the Atlantic States, especially southward, it occurs in meadows and along 

 ditches, and has a more lax panicle. Fig. 117. Var. m\jor (Torr.) Scribn. 

 Panicles narroivly lanceolate or oblong, rather densely flowered, the first glume 

 nearly equaling the rather narrow second one. {Eatonia intermedia Rydb.) — 

 Nfd, to Wash., s. to 111., Col., and Ariz. 



