MANUAL OF THE GRASSES OF THE UNITED STATES 



14. MOLINIA Schrank 



171 



Spikelets 2- to 4-flowered, the florets distant, the rachilla disarticu- 

 lating above the glumes, slender, prolonged beyond the upper floret 

 and bearing a rudimentary floret; glumes somewhat unequal, acute, 

 shorter than the first lemma, 1-nerved; lemmas membranaceous, 

 narrowed to an obtuse point, 3-nerved; palea bowed out below, 

 equaling or slightly exceeding the lemma. Slender tufted perennials, 

 with flat blades and narrow, rather open panicles. Type species, 

 Molinia caerulea. Named for J. I. Molina. 



1. Molinia caerulea (L.) Moench. (Fig. 341. )_ Culms erect, 50 

 to 100 cm tall; blades 2 to 7 mm wide, erect, tapering to a fine point; 

 panicle 10 to 20 cm long, purplish, the branches ascending, rather 

 densely flowered, mostly floriferous to the base; spikelets short- 

 pediceled, 4 to 7 mm long; lemmas about 3 mm long. % — Meadows 

 and fields, introduced in a few localities, Maine to Pennsylvania 

 (fig. 342) ; Eurasia. 



Figure 342.— Distribution of Molinia caerulea 



15. DIARRHENA Beauv. 



(Diarina Raf.) 



Spikelets few-flowered, the rachilla disarticulating above the glumes 

 and between the florets; glumes unequal, acute, shorter than the 

 lemmas, the first 1-nerved, the second 3- to 5-nerved; lemmas char- 

 taceous, pointed, 3-nerved, the nerves converging in the point, the 

 upper floret reduced; palea chartaceous, obtuse, at maturity the 

 lemma and palea widely spread by the large turgid beaked caryopsis 

 with hard shining pericarp; stamens 2 or 3. Perennials, with slender 

 rhizomes, broadly linear, flat blades, long-tapering below, and narrow, 

 few-flowered panicles. Type species, Diarrhena americana. Name 

 from Greek dis, twice, and arren, male, alluding to the two stamens. 



1. Diarrhena americana Beauv. (Fig. 343.) Culms slender, 

 about 1 m tall; leaves approximate below the middle of the culm; 

 sheaths pubescent toward the summit; blades elongate, 1 to 2 cm wide, 

 scabrous to pubescent beneath; panicle long-exserted, drooping, 10 to 

 30 cm long, the branches few, appressed, the lower distant; spikelets 

 10 to 18 mm long, at first narrow, the florets expanded at maturity; 

 lemmas 6 to 10 mm long. 91 (Diarina festucoides Raf.) — Rich or 

 moist woods, West Virginia to Michigan and South Dakota, south to 

 Tennessee, Arkansas, Oklahoma, and eastern Texas (fig. 344). 



