THE GENERA AND THEIR SPECIES. 129 



Varieties — 



P. supina. Panicle lax, branches deflcxed, spikelets 



green and purple. 



P. scvicea. Leaves not wrinkled. 



This species is the first weed to appear on the newly gravelled 

 path, and is responsible for most of the bare patches in lawns 

 during the winter. It will produce flowers and seeds when 

 only an inch high, coming up and blooming and ripening all 

 within a month. It blooms all the year round, even in December 

 and January. When growing in watery places its leaves lose their 

 wrinkles, and it is then known as P. sericea. 



87. P. compressa. Fields and dry places in the Northern 

 Hemisphere. June and July. Root perennial, moderately 

 creeping, fibres downy. Stem oval, decumbent or slanting, then 

 erect, smooth, constricted at base of panicle ; nodes four to seven, 

 uppermost half-way up the stem. Leaves folded in bud, short, 

 narrow, roughish at edges, hooded at apex, ribless, with median 

 lines, glaucous, Sheaths compressed, short, uppermost as long as 

 leaf ; ligule short, blunt. Panicle erect, dense when not in 

 flower, unilateral, branches in pairs, rough, acutely angular. 

 Spikelets ovate, small, florets three or more, webbed at base. 

 Glumes nearly equal, with three ribs, of which the middle one is 

 toothed. Outer palea obtuse, slightly longer than glumes, 

 with five ribs, of which the odd ones are hairy and the even ones 

 indistinct ; inner palea short, edged with green. 



Variety— 



P. polynorfa. Nodes numerous, uppermost more than 



half-way up the stem. 



This species is so much liked by sheep that it never flowers 

 when they are grazing on it. The crop is light, but what there is 

 of it is good. 



SS. P. pratensis. Common in meadows in the Northern 

 Hemisphere. June and July. Root perennial, creeping, stoloni- 

 ferous, reaching from five to fifteen inches in depth according to 



