LIV. CYPEKACE^. 879 



TRIBE III. HYPOLYTREdl. 



Spikelets 1-flowered, agglomerated in capitate heads or cymose panicles. 

 Flowers g , each with 2-4-6 closely imbricate glumes. Perianth 0. Stamens 2-3, 

 or 6-8. Style 2-8-fid, deciduous, or the base persistent. 



PRINCIPAL GENERA. 

 Hypolytrum. Lipocarpha. Hemicarpha. Diplasia. 



TRIBE IV. RHYNCHOSPOREJE. 



Spikelets usually few-flowered [flower solitary and axillary in Oreobolus]. 

 Glumes imbricate in 2 or several rows, the lower empty. Flowers usually poly- 

 gamous. Perianth 0, or composed of 6 bristles, rarely less, very rarely more (8-10) 

 [or of 6 2-seriate pieces in Oreobolus'] . Stamens 3, sometimes 6. Achene often 

 beaked by the persistent base of the style. 



PRINCIPAL GENERA. 



Arthrostylis. Caustis. Blysraus. Pleurostachys. 



Lepidospenna. Dulichium. Rhyncospora. Carpha. 



Schoenus. Cladium. Chsetospora. Oreobolus. 



TRIBE V. SCLERIErfl. 



Spikelets diclinous, the $ many-flowered, with glumes imbricate in 2 or several 

 rows, the lower ones sometimes empty. Perianth 0. Stamens 1-3, very rarely 5. 

 $ spikelets 1-flowered, with glumes imbricate in several rows. Perianth 0. Style 

 3-fid, equal at the base. Achene bony or crustaceous, usually seated on a 3-lobed 



disk. 



PRINCIPAL GENERA. 



Scleria. Diplacrum. 



TRIBE VI. CARICINE^J. 



Flowers monoecious or dioecious, in spikes, with glumes imbricate in several 

 rows. Perianth 0. $ spikes simple. Stamens 3-2. $> spikes simple or compound. 

 Pistil embraced by an inner scale with its back to the axis, 2-keeled (analogous to 

 the upper glumelle of Graminece), with edges usually joined and thus forming an 

 envelope or utricle (urceole, perianth, perigynium), persistent and accrescent, and 

 enclosing either the ovary only, or the ovary accompanied by a sterile setiform 

 pedicel. 



PRINCIPAL GENERA. 

 Carex. Elyna. 



Cyperacea are closely allied to Gramineee ; the latter being distinguished by their split leaf-sheath, 

 rounded culm with projecting nodes, dorsifixed anthers, usually plumose stigmas, fruit with pericarp 

 adhering to the testa, and always extruded embryo. The habit of Cyperacece is that of Eestiacea, but the 



