214 



GRAMINEAE. 



Vol. I. 



49. NOTHOHOLCUS Nash. 

 [Holcus L. Sp. PL 1047, in part. 1753.] 



Annual or perennial grasses with flat leaf-blades and spike-like or open panicles. Spike- 

 lets deciduous, 2-flowered; lower flower perfect, upper staminate. Scales 4; the 2 lower 

 empty, membranous, keeled, the first i-nerved, the second 3-nerved and often short-awned; 

 flowering scales chartaceous, that of the upper flower bearing a bent awn. Palet narrow, 

 2-keeled. Stamens 3. Styles distinct. Stigmas plumose. Grain oblong, free, enclosed in 

 the scale. [Greek, alluding to the reference of these grasses to the genus Holcus.] 



About 8 species, natives of the Old World. Type species : Holcus lanatus L. 



i. Nothoholcus lanatus (L.) Nash. Velvet-grass. 

 Meadow or Woolly Soft-grass. Fig. 517. 



Holcus lanatus L. Sp. PI. 1048. 1753. 



Softly and densely pubescent, light green, culms 

 li°-3° tall, erect, often decumbent at the base, simple. 

 Sheaths shorter than the internodes ; ligule 4"-i" long ; 

 blades i'-6' long, 2" -6" wide; spikelets 2" long, the 

 empty scales white-villous, the upper awn-pointed; 

 flowering scales 1" long, smooth, glabrous and shining, 

 the lower sparsely ciliate on the keel, somewhat obtuse, 

 the upper 2-toothed and bearing a hooked awn just 

 below the apex. 



In fields, meadows and waste places, Nova Scotia to 

 Ontario and Illinois, North Carolina and Tennessee. Also 

 on the Pacific Coast. Naturalized from Europe. Velvet 

 Mesquite. Old White-top. Salem-, Rot-, Dart- or 

 Feather-grass. Whites. Yorkshire-fog. White-timothy, 

 Calf-kill. June-Aug. 



50. ASPRIS Adans. Fam. 2 : 496. 1763. 

 [Aira L. Sp. PI. 63, in part. 1753.] 



Mostly annual grasses with narrow leaf-blades and contracted or open panicles. Spikelets 

 small, 2-flowered, both flowers perfect. Scales 4; the 2 lower empty, thin-membranous, 

 acute, subequal, persistent; the flowering scales usually contiguous, hyaline, mucronate or 

 2-toothed, deciduous, bearing a delicate dorsal awn inserted below the middle; palet a little 

 shorter than the scale, hyaline, 2-nerved. Stamens 3. Stigmas plumose. Grain enclosed 

 in the scale and palet, and often adhering to them. [Greek, from Theophrastus.] 



Six or seven species, natives of Europe. Type species : Aira praecox L. 

 Panicle open; flowering scales about 1" long; plants s'-io' tall. 1. A. caryophyllea. 



Panicle contracted; flowering scales about iy 2 " long; plants 2'-^ tall. 2. A. praecox. 



i. Aspris caryophyllea (L.) Nash. Silvery Hair-grass. Fig. 518. 



Aira caryophyllea L. Sp. PI. 66. 1753- 



Smooth and glabrous throughout, culms 5-10' tall, 

 erect from an annual root, simple, slender. Sheaths 

 mostly basal; ligule ii" long; blades i-2' long, involute- 

 setaceous; panicle 1 '-4' in length, silvery, shining, open, 

 the branches spreading or ascending, the lower 1' long 

 or less; spikelets i"-il" long, the empty scales acute; 

 flowering scales very acute, 2-toothed, 1" long, bearing 

 an awn ii"-2" long. 



In fields and waste places, eastern Massachusetts to 

 Ohio and Virginia. Also on the Pacific Coast. Local. 

 Naturalized from Europe. Mouse-grass. May-July. 



