E. vaginatum: stems tufted, one foot high or more, with one or two linear, almost subulate leaves; upper sheaths inflated, without any or only a very short blade; spikelet solitary, terminal, ovoid, deep olive-green; hypogynous bristles numerous, forming at length dense cottony tufts. - Bogs and wet moors. Fl. May.
E. polystachyum: leaves few, mostly radical, triangular, or channelled; stems 1-1 1/2 feet high, with a terminal umbel of 2 - 3 to 8-10 or more spikelets, the inner ones sessile, the outer ones more or less stalked, often drooping; spikelets ovoid or oblong; hypogynous bristles very numerous, forming dense cottony tufts, often attaining 1-1 1/2 inch in length. - Bogs and wet moors. Fl. May, June.
E. gracile is a small form, with very slender leaves, and few almost erect spikelets; and E. latifolium, a tallish slender plant, with the leaves nearly flat. Both are rare.