﻿GRASSES OF SCOTLAND. 35 



21. Agrostis alba. * 

 Marsh Bent- Grass. 



Specific Characters. — Floret of two palea? ; ligule long and acute ; 

 sheaths rough. (Plate XIII). 



Description. — It grows from eighteen inches to two feet high. The 

 root is perennial, tufted, somewhat creeping. Stem erect, round, 

 smooth, and polished ; bearing four or five leaves with roughish stri- 

 ated sheaths, (the roughness is felt only from above downwards, some- 

 times scarcely perceptible,) upper sheath longer than its leaf, crown- 

 ed with a long acute ragged ligule, slightly ribbed at the sides. 

 Joints smooth. Leaves rather short, flat, narrow, acute, very rough 

 on both surfaces, as well as on the edges. Inflorescence compound 

 panicled. Panicle erect, of a purplish tinge, with light-green florets, 

 the branches rough, slender, when in flower, spreading, arising from 

 the rachis mostly in fives, of various lengths, placed at equal distan- 

 ces ; the lowermost branches more or less tufted. Spikelets numerous, 

 small, erect, of one small awnless floret, concealed within the calyx. 

 Calyx of two narrow acute glumes, (Fig. 1), nearly of equal size, 

 without lateral ribs ; the larger glume the lowermost, minutely tooth- 

 ed its lohole length. Floret of two paleae, (Fig. 2) ; the outer palea, 

 ovate, minutely notched at the summit, without lateral ribs, furnished 

 at the base with a small tuft of short hairs. Inner palea about half 

 the length of the outer palea, cloven at the summit, pellucid, the mar- 

 gins entire. 



stolonifera, (Plate XIV). a variety with the branches 



of the panicles densely tufted. Sheaths roughish. Ligule long. Stem 

 procumbent at the base. Root creeping, throwing out long procum- 

 bent smooth stems, which take root at their joints. Frequently 

 found by the sides of ditches and wet places, and also on clayey soil 

 near the sea. Flowering in July and August. 



palustris, (Plate XIV). a variety with larger spikelets 



than usual. Outer palea awned a little beneath the summit, and fur- 

 nished with a small tuft of hairs at the base. Ligule long and point- 

 ed. Sheaths roughish. Commonly met with in damp shady stag- 

 nant places. Flowering in July and August. 



* Agrostis alba, Linn. Smith, Hooker, Greville, Lindley, Agrostis slo'wnifera Koch. 



