152 



Cyperacese. 



\.—CAREX. 



Glumes imbricated forming spikelets, staminate flowers without perianth 

 or bristles, stamens 2 — 3, pistillate flowers of a single compressed or triangular 

 ovary enclosed by an urceolate 2-toothed sac and crowned by 2 or 3 stigmas, 

 fruit minute enclosed in the sac {perigynium). Fig. p. 160. 



Spikelet solitary terminal, 573 

 Spikelets numerous compound (some flowers in each 

 spikelet staminate and some pistillate), 574 



573 Stamens and pistils on different plants, . . . C. dioica. 

 573 Stamens and pistils in separate flowers in the 



same spikelet, C. pulicaris. 



574 Spikelets short all similar, 575 

 574 Upper spikelets chiefly staminate usually more slender 

 than the lower and chiefly pistillate ones, 576 



575 Spikelets combined into a spike, 577 



575 Spikelets combined into a panicle, 580 

 576 Stigmas 2 (sometimes 3 in C. vulgaris), 581 



576 Stigmas 3, 582 



577 Spikelets in a crowded head \ — \\ in. . 



577 Spikelets in an oblong interrupted spike \ — 3 in. 



578 Fruit with a broad wing, 



578 Fruit scarcely winged, 579 



579 Terminal spikelet staminate at the base, 

 579 Terminal spikelet staminate at the top, 

 580 Spikelet with staminate flowers at the top only, 583 

 580 Spikelet with staminate flowers at the base only, 584 

 581 Pistillate spikelets short ovoid, 

 581 Pistillate spikelets long lanceolate or linear, 585 



C. divisa. 



578 

 C. arenaria. 



C. canescens. 

 C. disticha. 



C. vulgaris. 



582 Beak of perigynium short or none, 

 582 Beak of perigynium long bifid, 

 583 Stems stout, 589 



583 Stems wiry, 590 



584 Bracts long or leaflike, 591 

 584 Bracts none or subulate, 



585 Sheath-edges filamentous, 

 585 Sheath-edges not filamentous, 

 586 Perigynia glabrous, 592 



$86 Perigynia hairy, 593 



586 

 587 



C. leporina. 



C. stricta. 



C. acuta. 



