Cyperaceae

Leaf sheath closed or rarely open and then the perianth reduced to bristles or minute scales Cyperaceae

Flowers bisexual or unisexual but never enclosed in a utricle and never apparently separated into unisexual spikelets

Spikelets with 1–2 perfect flowers, other flowers male or sterile

Perianth scales or bristles absent

Glumes spirally imbricate (Fig. 46 a,m)

Leaves reduced to brown scales sheathing the culm Caustis

Leaves with distinct laminas