GLUMACE^ 395 



The glumes are ovate to oblong, acute, slender. The 

 female spikelets are four to six, acute, cylindrical, 

 long, inclined, stalked, sometimes compound below, 

 or male above. The glumes are narrow, brown, with 

 a green midrib, roughish at the tip. The perigynia 

 are ovoid, erect to spreading, dull green, narrowed 

 to the beak, ribbed, longer than the glumes, with 

 many closed ribs. The beak is short with two teeth. 

 The bracts are leaf-like. The fruit is oblong to ovoid, 

 elliptic, convex both sides, three-sided, yellow. There 

 are three stigmas. The nut is pear-shaped, triangular. 



This species is 3 to 5 ft. high. It flowers between 

 May and July, and is a herbaceous perennial. 



The flowers are wind-pollinated. The stigma 

 ripens in advance of the anthers. 



When ripe the nuts may fall in the water and be 

 water-dispersed. 



The names of this Sedge are Pond Sedge, Great 

 Common Sedge, Great Sedge. 



Carex riparia. — Fig. 111 gives mi idea of the tufted 

 character of the sedges, their social habit; the stems are 

 three-angled, the leaves keeled, the spikelets are large, 

 barren at the top, 



8g. The Grass Group. 

 The Order Graminaceae is one of the most wide- 

 spread in the whole realm of plants, not in indiv- 

 iduals, but in the universal distribution of the order, 

 grasses forming the most dominant type of vegeta- 

 tion. There are 3600 species and 310 genera. They 



