Agrostis. GRAMINE.E. 271 



with the rudiment of a second. Glumes somewhat unequal, the lower rather longer, 

 obtuse or acute, but pointless or awnless (except in n. 11), membranaceous. Floret 

 mostly shorter than the glumes, with a very short naked or hairy callus. Palets 

 one or two, very thin, the lower 3 - 5-nerved, pointless, naked, often bearing a slen- 

 der straight awn on the back usually much below the apex ; upper palet obsolete, or 

 present and shorter than or equalling the ovary, rarely nearly as long as the lower 

 palet. Scales 2, entire. Stamens mostly 3. Styles 2 ; stigmas feathery. Grain 

 free, terete, smooth. 



A rather large genus, widely distributed in cold and temperate climates ; the number of species 

 Is estimated at about 60, though over 200 are recorded. In high latitudes the species vaiy 

 greatly, especially as to the awn, the presence or absence of which has little value as a character. 

 They are mostly perennials, with slender low culms which form dense tufts. A few are useful as 

 pasture grasses, but on account of the general s])arseness of their foliage are not nmch valued for 

 mowing. 



* Spikelets with the rudiment of a second floret. — Podagrostis, Griseb. 



1. A. aequivalvis, Trin. Culm 1 to 2 feet high, erect, slender, smooth : leaves 

 flat, 4 to 6 inches long, the uppermost very short, and about a line wide, smooth or 

 nearly so, very pale green ; upper ligules about a line long ; sheaths smooth, shorter 

 than the internodes : panicle 2 to 6 inches long, loose, very narrow, smooth and 

 shining, the distant rays in whorls of 5 below, in pairs or solitary above, very un- 

 equal, the longer 1| to 2 inches long, nearly smooth and mostly flower-bearing above 

 the middle : spikelets from 1 to 1 1 lines long, mostly in pairs, one with a pedi- 

 cel shorter and the other with one longer than itself, sometimes purplish : glumes 

 nearly equal, acute, the upper 3-nerved : floret equalling the glumes, with a minutely 

 hairy callus, and a small hairy rudiment | or ^ its length : lower palet acute, 

 5-nerved; upper palet about as long as the lower. — Agrost. ii. 116. A. canina, 

 var. cequivalvis, Trin. in Bong. Veg. Sitch. 171. A. Ilillebmndii, Thurhev ; Boland. 

 in Trans. Cahf. Agric. Soc. 1864, 136. 



Calaveras County {Dr. Hillchrand) ; Mariposa Grove (Bolandcr) ; Oregon, Hall. Also Sitka 

 and Unalaschka. A perennial according to Trinius, but all our specimens lack the root and the 

 weak cuhn has much the appearance of an annual. Trinius describes the rudiment in the far 

 northern specimens as two-thirds the length of the floret, but it does not reach that in those col- 

 lected in California and Oregon. In the Oregon plant the panicle is shorter and the flowers pur- 

 plish, while the Calaveras County specimens are noticeable for the unusually pale green of both 

 panicle and foliage. 



* * Spikelets strictly 1-floivered, without the rudiment of a second floret. 



•»- Upper palet present., one third {or more) the length of the lower. — Agrostis 



proper. 



++ Panicle elongated. 



2. A. alba, Linn. Culms varying from a few inches to 2 feet high, sometimes 

 decumbent at base : leaves flat, short, smooth or roughened ; sheaths smooth ; ligule 

 short and truncate or long and acute : panicle slender, usually spreading when in 

 flower and more or less contracted afterwards, green, purplish or brownish, raj^s 

 roughish : spikelets one line long or less : glumes nearly equal, the lower slightly 

 longer : floret slightly sliorter than the glumes, the brief callus with some very minute 

 hairs ; lower palet very thin, 5- or 3-nerved, rarely with a short awn ; upper palet 

 I to J the length of lower. —^. stoloiiifera, Linn. ; Keichenb. L^on. Fl. Germ. i. 9, 

 t. 133-137, 139. A. vulgaris, With. ; Eeichenb. \. c, t. 130-132. 



A native of Europe, introduced in most of the cultivated portions of the State and of the 

 country, and exceedingly variable, its different forms having given ground for over 30 nomi- 

 nal species. In most works A. alba and A. vulgaris are kept distinct, perhaps from the fact that 

 they are recognized as difl'erent in agriculture, the only botanical character that (;an separate them 

 being the ditterence in thelength of the ligule. They "may be distinguished as follows : — var. alba 



