GRASS FAMILY. 373 



ceeds harvest ; and thus the ground is left exposed to the injurious in- 

 fluence of the scorching sun. The clover, however, when present in suf- 

 ficient quantity, soon springs up and affords a shelter to the soil ; and, 

 when the land is good, the green grass (PoA PRATENSIS, L.), comes in, 



spontaneously, as the clover disappears. The seed, of Timothy, is 

 usually sown in autumn, among, and immediately after Wheat and 

 Eye ; though it answers very well, when sown early the ensuing spring. 



6. AGROS'TIS, L. BENT-GRASS. 



[Greek, Agros, a field ; its usual place of growth.] 



Spikelets in an open panicle, 1 -flowered. Glumes nearly equal, often 

 longer than the paleae, pointless. Palece very thin, pointless, naked at 

 the base; the lower 3-5-nerved, sometimes awned on the back, the 

 upper often minute or wanting. Stamens usually 3. Mostly perennials 

 with slender caespitose culms. 



1. A. VULGA'RIS, With. Culms slender, mostly erect; leaves lance- 

 linear ; panicle loose, ovoid-oblong in its outline, usually purple ; pu- 

 leae awnless, the lower one twice the size of the upper one ; ligule 

 truncate, very short. 



COMMON AGROSTIS. Herd-grass (of Penn.) Red-top. 



Root perennial, creeping. Culms csespitose, very slender, erect or ascending, 1-2 feet 

 high. Leaves 3-6 or 8 inches long, nerved, scabrous ; sheaths striate, smooth. Panicle 

 mostly purple the branches capillary, alternatingly semi-verticillate, smoothishor often 

 scabrous. Glumes smooth, except on the keel, lanceolate, acute, finally expanding. 

 1'alece membranaceous, smooth at base, the lower one nearly as long as the glumes, 

 the upper one very small, retuse. 



Pastures and moist meadows : introduced. Native of Europe. Fl. July. Fr. August. 



Obs. This grass is somewhat variable in its botanical characters, 

 as may be inferred from one of the specific names it has received, viz. : 

 A. polymorpha. It is often cultivated in some districts of the country, 

 and answers a tolerably good purpose in wet or swampy meadows, which 



FIG. 253. A spikelet of Timothy (Phleum pratense). 254. The floret removed from the 

 glumes. 



