Fig. 175: Scirpus fluviatilis: a-d, achenes, showing variation in shape (cross section), 

 X 6; e, flower, style slender and trifid, the bristles unequal in length, X 3; f and g, 

 awned scales, X 4; h, achene, the subtending bristles unequal in length, X 4; i, spikelet, 

 X ly-,; j, rhizome, tubers and sharply triangular culms, X %; k, inflorescence with 

 nearly sessile rays and longer primary rays, X %; 1, habit, showing rhizomes, tubers, 

 sheathing culm leaves and umbellate inflorescence with the involucral leaves unequal 

 in length, X %• (From Mason, Fig. 148). 



