explanatio:n' of plate yi. 



CAREX. — (1) C. trisperma, upper part of a stem in fruit; (2) enlarged 

 spike displayed, ■with three staminate and two pistillate flowers; (3) a 

 scale, and (4) a ripe perigynium, of the latter; Avitli (5) a section of the 

 perigynium near the base, and of the contained achene. — (6) C. straminea, 

 var. brevior, summit of a fruiting plant; (7) a spike enlarged ; (8) scale 

 of a pistillate flower; (9) the winged perigynium and the contained 

 achene cut across; (10) detached achene with persistent style aijd stig- 

 mas. — (11) C. umbellata, Avhole plant; (12) a perigynium and its scale; 



(13) cross-section toward the base of perigynium and its contained achene; 



(14) detached achene with its persistent style and stigmas. — C. bullata; 



(15) upper part of plant in fruit, with one pistillate and two staminate 

 spikes; (16) one of its staminate flowers with the scale ; (17) a pistillate 

 scale, and (18) mature perigynium; (19) longitudinal section of the lat- 

 ter, showing the achene and its style, and (20j cross section of the same. 



