Note: Do not rely on this information. It is very old.
Cyperus
Cyperus, a large genus of plants giving its name to the order Cyperaceae, the sedges. It has a triangular stem, bearing leaves in three rows below, and clusters of distichous spikelets above, with a leafy involucre. The genus belongs mainly to the tropics, only two rare species existing in England. Several kinds have edible roots or tubers.