GENUS 50. 



GRASS FAMILY. 



21 5 



2. Aspris praecox (L.) Nash. Early Hair- 

 grass. Fig. 519. 



Aira praecox L. Sp. PI. 65. 1753. 



Glabrous and smooth throughout, culms 2'-^' tall, 

 erect, from an annual root, simple, rigid. Sheaths 

 clothing the whole culm, the upper one often enclosing 

 the base of the panicle; ligule about li" long; blades 

 i' long or less, involute-setaceous ; panicle contracted, 

 strict, i'-i' in length; spikelets about ij" long, the 

 empty scales acute; the flowering scales acuminate, 

 2-toothed, about li" long, bearing an awn i'$"-2" long. 



In dry fields, southern New Jersey and Pennsylvania 

 to Virginia. Naturalized from Europe. May-July. 



51. DESCHAMPSIA Beauv. Agrost. 91. pi. 18. f. 3. 1812. 



Perennial grasses with flat or involute leaf-blades, and contracted or open panicles. 

 Spikelets 2-flowered, both flowers perfect, the hairy rachilla extended beyond the flowers. or 

 rarely terminated by a staminate one. Scales 4 (rarely more), the 2 lower empty, keeled, 

 acute, membranous, shining, persistent ; the flowering scales of about the same texture, 

 deciduous, bearing a dorsal awn, the apex toothed. Palet narrow, 2-nerved. Stamens 3. 

 Styles distinct. Stigmas plumose. Grain oblong, free, enclosed in the scale. [In honor of 

 J. C. A. Loiseleur-Deslongchamps, 1774-1849, French physician and botanist.] 



About 20 species, inhabiting cold and temperate regions, a few occurring in the high mountains 

 of the tropics. Besides the following, some 6 others occur in the western parts of Nort America. 

 Type species : Aira caespitosa L. 



Upper flowering scale reaching or extending beyond the apex of the empty scales. 



Flowering scales about i%" long, erose-truncate ; leaves flat. i. D. caespitosa. 



Flowering scales about 2" long, acute or obtuse ; leaves involute. 2. D. flexuosa. 



Empty scales extending much beyond the upper flowering scale. 3. D. atropurpurea. 



. i. Deschampsia caespitosa (L.) Beauv. Tufted Hair-grass. Fig. 520. 



Aira caespitosa L. Sp. PI. 64. 1753. 



D. caespitosa Beauv. Agrost. 160. pi. 18. f. 3. 



1812. 



Culms 2-4 tall, erect, simple, smooth and glabrous. 

 Sheaths much shorter than the internodes; ligule I "-3" 

 long; blades flat, i"-i$" wide, smooth beneath, strongly 

 scabrous above, the basal ones numerous, one-quarter 

 to one-half as long as the culm, those of the culm 

 2'-6' long; panicle open, 3'-o/ in length, the branches 

 widely spreading or ascending, often somewhat flexu- 

 ous, naked at the base, the lower 2'-s' long; spikelets 

 iJ"-2" long; flowering scales about li" long, erose- 

 truncate at the apex, the awns somewhat shorter or a 

 little longer, the upper scale reaching to or extending 

 beyond the apices of the empty ones. 



Newfoundland to Alaska, south to New Jersey, Illi- 

 nois, Minnesota and in the Rocky Mountains and Sierra 

 Nevada to New Mexico and California, mostly in wet 

 soil. Also in Europe and Asia. Hassock-grass, Bull- 

 poll, Bullpates, Windlestraw. July-Aug. 



