GRAMINEAE. 



i. Koeleria cristata (L,. ) Pers. 

 (Fig. 444.) 



Koeleria. 



Aira cristata L- Sp. PI. 63. 1753. 

 Koeleria cristata Pers. Syn. i: 97. 1805. 

 Koeleria nitida Nutt. Gen. i: 74. 1818. 

 Koeleria cri stata var. gracilis A. Gray, Man. 591. 



Culms i-2)4 tall, erect, simple, rigid, smooth, 

 often pubescent just below the panicle. Sheaths 

 often shorter than the internodes, smooth or sca- 

 brous, sometimes hirsute; ligule YZ" long; leaves 

 I / -I2 / long, j4 // -^/4 // wide, erect, flat or invo- 

 lute, smooth or rough, often more or less hirsute; 

 panicle i / -7 / in length, pale green, usually con- 

 tracted or spike-like, the branches erect or rarely 

 ascending, i / long or less; spikelets 2-5-flowered, 

 2 // -3 // long, the scales rough, acute, the empty ones 

 unequal; flowering scales i^ // -2 // long, shining. 



In dry sandy soil, especially on prairies, Ontario to 

 British Columbia, south to Pennsylvania, Nebraska, 

 Texas and California. Also in Europe and Asia. Very 

 variable. July-Sept. 



68. CATABROSA Beauv. Agrost. 97. pi. 19. f. 8. 1812. 

 A perennial grass, with soft flat leaves and an open panicle. Spikelets usually 2-flow- 

 ered. Two lower scales empty, thin-membranous, much shorter than the flowering ones, un- 

 equal, rounded or obtuse at the apex; flowering scales membranous, erose-truncate. Palet 

 barely shorter than the scale. Stamens 3. Styles distinct. Stigmas plumose. [Greek, in 

 allusion to the erose top of the flowering scales.] 



A monotypic genus of arctic and mountainous 

 regions of the northern hemisphere. 



i. Catabrosa aquatica .(I,.) Beauv. 

 Water Whorl-grass. (Fig. 445.) 



Aira aquatica L. Sp. PI. 64. 1753. 

 Catabrosa aquatica Beauv. Agrost. 157. 1812. 



Smooth and glabrous, culms 4 / -2 tall, erect, from 

 a creeping base, bright green, flaccid. Sheaths 

 usually overlapping, loose; ligule i^ // -2^ // long; 

 leaves i^'-5' long, 1"-$" wide, flat, obtuse; pan- 

 icle i '-8' in length, open, the branches whorled, 

 spreading or ascending, very slender, Vz'-z' long; 

 spikelets iX"-!^"" long, the empty scales rounded 

 or obtuse, the first about half as long as the second, 

 which is crenulate on the margins; flowering scales 

 i"-iX" long, 3-nerved, erose-truncate at the apex. 



In water or wet soil, Labrador and Quebec to Alaska, 

 south to Nebraska, Colorado and Utah. Also in Europe 

 and Asia. Summer. 



69. MELICA L. Sp. PI. 66. 1753. 



Perennial grasses, with usually soft flat leaves and contracted or open panicles. Spike- 

 lets i-several-flowered, often secund, the rachilla extended beyond the flowers and usually 

 bearing 2-3 empty club-shaped or hooded scales, convolute around each other. Two lower 

 scales empty, membranous, 3-s-nerved; flowering scales larger, rounded on the back, 7-13- 

 nerved, sometimes bearing an awn, the margins more or less scarious; palets broad, shorter 

 than the scales, two-keeled. Stamens three. Styles distinct Stigmas plumose. Grain 

 free, enclosed in the scale and palet [Name used by Theophrastus for Sorghum; said to be 

 in allusion to the sweet culms of some species.] 



Abt 30 species, inhabiting tem P erat e regions. Besides the following, some 15 others occur 

 in the Rocky Mountains and on the Pacific Coast. 

 Second scale much shorter than the 3~5-flowered spikelets. 



Spikelets few; branches of the panicle spreading or ascending. i. M. diffusa. 



pikelets usually numi-mus; branches of the panicle erect. 2. M. parviflora. 



cond scale nearly equalling the 2-flowered spikelet. 3 M mutica 



t 



