280 GRASSES OF BRITAIN. 



Bromus SQUARROSUS. 



Corn Brome- Grass. 



Plate CXXVIII. 



Specific Characters. — Awns divaricating when dry. Outer palea 

 nine-ribbed, twice the breadth greater than half its length. 



Description. — Root annual, fibrous. Stem erect, hollow, round, 

 smooth, striated and polished, from nine to eighteen inches high ; bear- 

 ing four or five leaves with striated sheaths shorter than their leaves ; the 

 upper sheath slightly roughish, the lower sheaths soft and pubescent. 

 Ligules prominent and ragged. Joints usually four, the upper ones 

 seldom covered by the sheaths. Leaves flat, narrow, linear-lanceo- 

 late, rough on both surfaces, especially when felt from point to base, 

 the lower ones less harsh, and frequently with soft downy hairs. In- 

 florescence racemed, at first erect, at length drooping to a side, the 

 rachis and branches rough. Spikelets, when young, oblong-lanceo- 

 late, in seed more oval and subcompressed, (not hairy,)usually of ten 

 florets and two glumes, frequently tinged with reddish brown ; apex 

 of large glume situated half-way between the base of the glume and the 

 summit of the second floret of the same side, (Fig. 1.) Glumes two, 

 unequal, membranous at the margins, roughish on the keels ; outer 

 glume the smaller, three-ribbed ; inner glume five-ribbed. Florets of 

 two paleee, the outer palea of lowermost floret longer than the glumes ; 

 nine- ribbed, the marginal ribs the most distinct; it is either bifid or 

 entire at the summit, membranous and glossy at the margins, not twice 

 as long as broad, and when opened the superior margins exhibit an 

 obtvise angle ; inner palea much shorter than the outer, not reaching 

 further up than to the base of the awn, thin, obtuse, white and membra- 

 nous, furnished with two green marginal ribs fringed with stout white 

 hairs. Awns erect, rough, at length divaricating, arising from below 

 the summit of the outer palea, and about the length of the palea ; 

 those of the two lowermost florets shorter than the palea. Ovarium 

 hairy on the summit. Styles two, short, arising from the side. 



Bromm squaiTosm, Linn., Huds., Eng. Bot., Schrad., Koch, K until, Hooker, Smith, 

 With., Lindley. Serrofalrvs squarrosits, Babington. 



