94 



GRASSES OF SCOTLAND. 



three-ribbed. Branches and rachis smooth to the touch. Leaves 

 rough on the inner surface. (Plate XLII.) 



Description. — It grows from six to twelve inches high. The root 

 is perennial, creeping. Stem erect, round and smooth, decumbent at 

 the base ; bearing three or four leaves with smooth tumid sheaths ; 

 the upper sheath longer than its leaf, crowned with an obtuse decur- 

 rent ligule ; second sheath most frequently reaching beyond the first 

 joint. Joints four, smooth. Leaves mostly folded and compressed, 

 very seldom flat, roughish on the inner surface, smooth behind. In- 

 Jlorescence mostly simple panicled, seldom compound. Panicle erect, 

 close, spreading whilst in flower, unilateral, leaving the rachis be- 

 hind bare ; branches smooth to the touch, arranged on the rachis in 

 pairs, threes, or fives ; the lower branches never deflexed. Spikelets 

 linear (Fig. 3), of six to ten florets ; the summit of the lowermost 

 floret extending considerably beyond the large glume of the calyx. 

 Calj/x of two unequal membranous glumes (Fig. 1 ), three-ribbed ; 

 the outer glume rather more than half the length of the inner one. 

 Florets not icebbed, of two palese (Fig 2) ; the outer palea of lower- 

 most floret terminating in an acute point ; five-ribbed (Fig 4), smooth 

 above, and slightly hairy at the base. Inner palea about equal in 

 length to the outer palea, with two green marginal ribs delicately 

 fringed. 



Obs. — Poa maritima is very likely to be confounded with some va- 

 rieties of Poa distans, especially those in which the branches are not 

 deflexed ; it is, however, distinguished by the rachis and branches be- 

 ing smooth to the touch. The root creeping. Central rib of the 

 outer palea extending to the very summit, giving an acute appearance 

 to the palea. Leaves almost always folded and scarcely ever flat ; — 

 whereas in P. distans the rachis and branches are rough ; the root fi- 

 brous ; central rib of the outer palea not extending to the summit, 

 leaving the upper membranous part obtuse ; leaves almost always 

 flat, and scarcely ever folded. (See Plate XLI.) 



From Poa procumbens, in the root being creeping ; rachis and 

 branches smooth to the touch ; leaves narrow and almost always 

 folded ; ribs of the glumes distinct but not prominent ; central rib 

 of the outer palea not extending beyond the summit ; — whereas in P. 

 procumbens the root is fibrous ; rachis and branches rough ; leaves 



