202 GRASSES OF BRITAIN. 



POA BULBOSA. 



Bulbous Meadoiv-Gi-ass. 

 Plate LXXXIX. 



Specific Character. — Florets webbed. Ligules long and acute. 

 Stem and sheaths smooth. 



Description. — Root perennial, bulbous. Stem round, smooth, hol- 

 low, and striated, from five to nine inches high, bearing four or five 

 leaves, with smooth striated sheaths ; the upper sheath much longer 

 than its leaf. Ligule of upper sheath long and pointed, about twice 

 as long as broad. Joints usually three, the upper situated below the 

 centre of the stem, and frequently covered by the second sheath. 

 Leaves flat, acute, roughish on the edges and inner surface, smooth 

 behind. Inflorescence panicled, the branches rough, arising alter- 

 nately on the rachis, generally in pairs. Spikelets ovate, green, or 

 tinged with purple, composed of two glumes and three or four florets. 

 Glumes about equal, three-ribbed, toothed on the upper half of the 

 keels. Florets longer than the glumes, copiously webbed at the base, 

 of two palese, the outer palea of lowermost floret five-ribbed; the 

 dorsal and marginal ribs hairy, the intermediate ribs naked ; the 

 inner glume a very little shorter than the outer, thin, whitish, nar- 

 row, acute, furnished with two green ribs, minutely fringed. Styles 

 two, distinct. Stigmas feathery. Filaments capillary, three. An- 

 thers notched at each end. Scales acute, notched. 



Ohs. — Poa bulbosa belongs to that division of Poa in which the 

 florets are webbed at the base. 



It is distinguished from Poa pratensis in the ligules being acute ; 

 root bulbous-like ; — while in Poa pratensis the ligules are obtuse, and 

 the root fibrous. 



Poa bulbosa is distinguished from Poa trivialis in the sheaths being 

 smooth ; marginal ribs of outer palea hairy ; — whereas in Poa tri- 

 vialis the sheaths are rough, and the marginal ribs of the outer palea 

 naked. 



Poa bulbosa is distinguished from Poa compressa in the ligules being 



Poa bulbosa, Linn., Kunth, Koch, Smith, Hooker, Knapp, With., Lind., Bab. 



