GRASSES OF SCOTLAND. 57 



thin, about equal in length to the outer palea, and very minutely 

 fringed at the margins. Second floret on a very short smooth pedicle, 

 but in other respects similar to the one below. 



Ohs. — This grass is very closely allied to Aira prcecox, especially 

 Avhen young, but differs from it in being generally a taller plant, 

 with smaller spikelets ; the branches of the panicle more spreading, 

 especially when in seed ; the cah-x somewhat of a quadrangular form, 

 rounded at the base ; the awn arising from a little beneath the 

 centre of the palea ; — whereas in A. prcEcox the panicle is close, 

 the cal}-x of a triangular form, nearly acute at the base, and the awn 

 arises from nearer the base. (See Plate XXV. Figs. 1, 2, 3.) 



This grass to the farmer is of minor consideration, as it produces 

 but little foliage, which soon withers. It grows on dry gravelly places, 

 and is frequent in England, Scotland, and L'eland, as well as in Ger- 

 many, France, and Italy, but has not been discovered in Lapland or 

 America. Its limit of altitude about 1500 feet above the sea. 



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

 of July. 



39. Aira prjecox. * 

 Early Hair- Grass. 



Specific Characters. — Awn longer than the palea, arising from a 

 little above the base. Panicle close. (Plate XXV.) 



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

 annual, fibrous. Stem erect, round and smooth, bearing four or five 

 leaves, with rough, striated, slightly inflated sheaths, (the roughness 

 is mostly on the upper part of the sheaths, very perceptibly felt when 

 the finger is passed from below upwards, but smooth in the opposite di- 

 rection) ; the upper sheath longer than its leaf, crowned with a lan- 

 ceolate membranous ligule, closely embracing the stem ; the lower 

 sheaths shorter than their leaves. Joints smooth. Leaves mostly all 

 on the stem, narrow, roughish to the touch, especially the upper- 

 most ones. Injlorescence simple panicled; of a greenish silvery 

 appearance. Panicle erect, close ; the branches roughish ; rachis 



• Aira pmcox, Smith, Hooker, Lindlcy, Greville. 



