180 GRASSES OF BRITAIN. 



Phleum ASPERUM. 



Rough Cafs-tail Grass. 



Plate LXX IX. 



Specific Characters. — Glumes wedge-shaped. Keels rough. 



Desci'iption. — Root perennial, fibrous. Stem erect, round, hollow^ 

 smooth, from six to eighteen inches high, bearing four or five leaves 

 with somewhat roughish inflated sheaths, the upper sheath longer than 

 its leaf. Ligule prominent and pointed, twice as long as broad. 

 Joints usually four, all covered by the sheaths, the upper joint situ- 

 ated above the centre of the stem. Leaves flat, acute, roughish on 

 both surfaces as well as on the edges. Lvflorescence panicled, from 

 two to five inches in length, compact, with the branches arranged 

 mostly in threes. Spikelets numerous, compressed, composed of two 

 glumes and one floret. Glumes of equal lengths, pointed, rough, 

 wedge-shaped, variegated with green and wliite, the inner mar- 

 gins membranous, straight, and obtuse at the summit. Floret 

 about one-third shorter than the glumes, of two paleae, the outer pa- 

 lea roughish, obscurely five-ribbed, hairy on the upper part of the 

 central rib, and obtuse at the summit ; inner palea rather smaller, 

 folded at the margins. Filaments three, capillary. Anthers cloven 

 at each end. Styles two, distinct. Stigmas feathery. Seed cylin- 

 drical, loose. 



Obs. — Phleum asperum is distinguished from Phleum pratense in 

 the glumes being wedge-shaped, pointed. Keels rough. Floret entire 

 at the summit ; — whereas in Phleum pratense the glumes are more of 

 a cylindrical form, terminating in two prominent rough awns. Keels 

 fringed with conspicuous bristle-like hairs. Floret jagged and mi- 

 nutely awned at the summit. 



Phleum asperum is distinguished from Phleum Michelii in the 

 glumes being wedge-shaped, swelling upwards, abrupt at the inner 

 margins. Keels rough, not hairy ; — whereas in Phleum Michelii the 

 glwnes are lanceolate, acute. Keels very hairy. 



Pldeum asperum is distinguished from Phleum arenarium in the 



Phleum asjierum, Koch, Smith, Hooker, Bab., Lind., Schrad, Phleum paniculatiun, 

 Huds., Eng. Bot., Knapp. PhaJaris aspera, Retz, Willd., Host. 



