MEADOWS, FIELDS AND PASTUBES— SPRING 121 



rather long stalks ; the stem-leaves are smaller, few in number, 

 with shorter stalks. Sometimes both male and female flowers 

 grow on the same plant, but often the jDlant produces the one kind 

 only. They are arranged in long, leafless panicles ; and the outer 

 lobes of the perianth of the female flowers are turned back on the 

 peduncle, while the inner are enlarged and swollen, and close over 

 the fruit. 



The other species — the Sheep's 

 Sorrel (i?. Acetosella) — is a much 

 smaller plant, seldom reaching a 

 foot in height, and often only three 

 or four inches. It grows abund- 

 antly in dry pastures and on 

 heaths, flowering from May to 

 July. It is much more slender 

 than the Common Sorrel ; and 

 its leaves, wliich are also acid, 

 are all very narrow, and generally 

 either arrow-shaped or spear- 

 shaped at the base. The flowers 

 are in very slender, terminal 

 panicles, the males and the females 

 always on separate plants ; and 

 the latter differ from those of the 

 last species in that all the segments 

 of the perianth close over the fruit. 



Coming now to the monocoty- 

 ledonous plants, we have first to 

 note three flowers of the order 

 Orchidacece, the general features 

 of which are described in Chapter 

 XVIII ; and the reader is advised 



to refer to this short account of the leading characteristics of the 

 group before attempting to identify the present species. 



The first is the Twayblade {Listera ovata), frequently seen in 

 moist pastures, as well as in woods, flowering from May to July. 

 The stem of this plant is usually from one to two feet high, with a 

 few sheathing scales at the base ; and the species can be recognised 

 at once by its two broad oval leaves, almost exactly opposite one 

 another, from two to four inches long, and about six inches from 

 the ground. The flowers are of a yellowish-green colour, in a 



rox-TAiL Grass. 



