12 GRASSES OF SCOTLAND. 



Description. — It grows from one to three feet high. The root is 

 perennial, fibrous. Stem erect, round, smooth, and striated, bearing 

 four or five leaves, with smooth, somewhat inflated sheaths ; the upper 

 sheaths longer than its leaf, crowned with a short, obtuse ligule. 

 Joints smooth. Leaves flat, acute, generally rough on both surfaces ; 

 the radical leaves mostly smooth on the under surface. Inflorescence 

 compound panicled. Panicle erect, from one to two inches in length, 

 of an oblong form approaching to cylindrical, compact, close, with 

 very short branches arranged on all sides of the rachis. Spikelets 

 numerous, compressed, imbricated, of an ovate form, erect, turning 

 of a light greyish brown with age ; of one awned floret, equal in length 

 to the calyx. Calyx of two glumes (Fig. 1.) of equal lengths, acute, 

 united at the base, fringed on the keels and lateral ribs, which are of 

 a light green. Floret of one palea of an ovate-oblong form, with two 

 green ribs on each side ; furnished with a long slender, dorsal awn, 

 arising from a little above the base, and extending more than half its 

 length beyond the summit of the palea ; upper part of the keel more 

 or less hairy. Anthers prominent, yellow. Styles united. Stigmas 

 separate, slender, and feathery. Seed ovate. 



Ohs.— Alopecurus pratensis is distinguished from Alopecurus geni- 

 culatus in the upper leaf being not more than half the length of its 

 sheath ; awn projecting more than half its length beyond the palea ; 

 palea (when viewed from within, and made flat by throwing open the 

 sides (Fig. 4.) of a conical form, with four, broad distinct green ribs ; 

 glumes of a diflferent shape, more acute (Fig. 1); — ^whereas in A. geni- 

 culatus the upper leaf is about the length of its sheath; aivn project- 

 ing half its length beyond the palea ; palea (when viewed from with- 

 in (Fig. 4.) obtuse, slightly notched in the centre, with four rather in- 

 distinct green ribs, tinged with purple at the summit. 



From Alopecurus fuhus, in the awn projecting more than half its 

 length beyond the palea ; — whereas in A.fulvus the awn does not pro- 

 ject beyond the palea. (Plate V.) 



From Alopecurus agrestis, in the stem and sheaths being perfectly 

 smooth : — whereas in agrestis the stem and sheaths are rough. (Plate 



™-) 



From Alopecurus alpinus, in the panicle being longer ; awn arising 



a little above the base, and projecting more than half its length beyond 

 the palea ; whereas in A. alpinus the panicle is not an inch in length -^ 



