﻿90 GRASSES OF SCOTLAND. 



distinctly webbed, suspending the calyx, and the outer palea three- 

 ribbed. (See Plate XXXVII.) 



From Poa pratensis, in the florets not being webbed, and the upper 

 sheath about equal in length to its leaf ; — whereas in P. pratensis the 

 lower florets are distinctly webbed, suspending the calyx ; and the up- 

 per sheath much longer than its leaf. (See Plate XXXI.) 



This is a rare grass, found on Ben-Lawers and the Clova mountains ; 

 is also a native of Switzerland and the Arctic regions. It possesses 

 no particular merits worthy the notice of agriculturists. 



Flowers in the third week of June, and ripens its seed about the 

 end of July. 



60. Poa ANNUA.* 

 Annual Meadow- Grass. 



Specific Characters. — Florets not webbed. Outer palea five-ribbed. 

 Leaves smooth on both surfaces. Rachis and branches smooth. 

 (Plate XL.) 



Description. — It grows from five to fifteen inches high. The 

 root is perennial, somewhat creeping, throwing out fibres at the 

 lower joints. Stem ascending, often procumbent at the base, 

 flattish, smooth, bearing four or five leaves, with smooth com- 

 pressed sheaths ; the upper sheath longer than its leaf, crowned 

 with a thin membranous somewhat acute ligule. Joints about four, 

 smooth. Leaves of a light-green, sword-shape, flat and flaccid, fre- 

 quently crumpled at the margins, smooth on both surfaces, rough at 

 the edges. Inflorescence compound panicled. Panicle erect, in its 

 outline of a triangular form, spreading, the branches smooth, mostly 

 in pairs, inclining to one side, leaving the smooth rachis visible its 

 whole length behind. Spihelets ovate-oblong, usually of five to eight 

 awnless florets, frequently variegated with green, white, and purple ; 

 the summit of the lowermost floret extending beyond the large glume 

 of the calyx. Calyx of two unequal acute glumes (Fig. 1), three- 

 ribbed, the dorsal rib minutely toothed on the upper part. Florets 

 not webbed, of two palese, (Fig. 2) ; the outer palea of lowermost floret 



* Poa annua, Linn. Smith, Hooker, Greville, Koch. 



