GRAMINEAE (GRASS FAMILY) 47 



14. PHALARIS L.i Canary Grass 



Annuals or perennials with flat leaves, inflorescence spike-like, capitate, or 

 a narrow panicle. Spikelets crowded, l-flbwered. Glumes 5; the first and 

 second about equal in length, strongly compressed laterally, usually wing- 

 keeled; third and fourth glumes much smaller or reduced to mere rudiments; 

 fifth glume subtending a palet similar to itself and a perfect flower. Sta- 

 mens 3. Styles distinct; stigmas plumose. Grain oblong, free, smooth, in- 

 closed in the indurated glume. 



Outer glumes not "Ringed; inflorescence a narrow panicle . . .1. P, arundinaces. 

 Outer glumes broadly winged; inflorescence a spike-like panicle . . 2. -P. caroliniana, 



1. Phalaris arundinacea L. Sp. PI. 55. 1753. Stout erect glabrous peren- 

 nial, 6-15 dm. high: leaves 8-25 cm. long, 6-16 mm. wide: panicle 7-20 cm. 

 long, dense and contracted: spikelets 5-6 mm. long; outer glumes 3-nerved; 

 third and fourth glumes less than one half as long as the fifth; fifth glume 

 about three fourths as long as the spikelet, pubescent with long appressed 

 silky hairs. Reed Canary Grass. — Throughout our range. 



2. Phalaris caroliniana Walt. Fl. Car. 74. 1788. . Comparatively slender 

 annual, 3-10 dm. high: leaves rather short, 5-15 cm. long, 4-10 mm. wide: 

 spike-like panicle oblong, densely flowered, 2-10 cm. long: spikelets 5 mm. 

 long; third and fourth glumes less than one half as long as the fifth; fifth 

 glume about two thirds as long as the spikelets, acuminate, pubescent with 

 long appressed hairs. — ^Infrequent in our range. 



15. HIEROCHLOE Gmel. Holy Grass. Vanilla Grass 



Aromatic perennials with flat leaves and contracted or open panicles. 

 Spikelets 3-flowered, the terminal flower perfect, the others staminate. 

 Glumes 5; the first and second nearly equal, acute, glabrous; the third and 

 fourth somewhat shorter, obtuse, entire, emarginate, 2-toothed or 2-lobed, 

 with or without an awn, inclosing a palet and perfect flower. Stamens in the 

 staminate flowers 3, in the perfect, 2. Styles distinct; stigmas plumose. 

 Grain free, inclosed in the glunies.^(Saj)astona Schrank.) 



1. Hierochloe odorata (L.) R. & S. ^yst. 2: 513. 1817. Slender sweet- 

 scented stoloniferous perennial, 3-6 dm. high: lower leaves elongated, 1-2 dm. 

 long, 2-6 mm. wide; the upper ones 1-5 cm. long: panicle brownish, open, 4- 

 10 cm. long, the branches in pairs: spikelets yellowish-brown and purple, 4-6 

 mm. long; first and second glumes acute; third and fourth villous and strongly 

 ciliate, awn-pointed. Hierochloe horealis. — ^Throughout our range. 



16. ARISTIDA L. Thbee-awned Grass 



Tufted annuals or peremiials with narrow, often involute-setaceous leaves. 

 Spikelets narrow, 1-flowered, in terminal more or less expanded panicles. 

 Glumes narrow, carinate; lemma rigid and convolute, bearing three awns oc- 

 casionally tmited at the base, the lateral awns rarely wanting or reduced to 

 rudiments; palet 2-nerved. Stamens 3. Styles distinct; stigmas plumose. 

 Grain free, tightly inclosed in the lemma. 



First and second glumes subequal 1. A. pligantha. 



First glume about one half as long as the second 2. A. longiseta, 



1. Aristida oligantha Michx. Fl. Bor. Am. 1: 41. 1803. Tufted annual, 

 2-4 dm. high, with slender dichotomousljrbranched culms and loose sheaths: 

 leaves smooth, 2-15 cm. long, 1-2 mm. wide: spikelets few, in a lax spike-like 

 raceme or panicle; first glume 5-nerved, occasionally 7-nerved at base, equal- 

 ing or somewhat shorter than the second, which bears an awn 4-8 mm. long; 

 lemma shorter than the first glume; awns divergent or spreading, middle one 

 4-6 cm. long, lateral ones somewhat shorter. — Infrequent; Colorado. 



