Herbs, perennial. Roots occasionally with tubers. Rhizomes stout. Leaves erect, terete; sheath with ligule apically entire or 2-lobed. Inflorescences spikelike racemes, scapose; scapes shorter than to longer than leaves. Flowers bisexual, of 1 type, short-pedicellate; tepals 6, in 2 series, distinct, yellow-green, conchiform; stamens 4 or 6; anthers nearly sessile; pistils 6, 3 fertile, 3 sterile or 6 fertile, separating when mature; ovules 1 per locule; styles absent. Fruits schizocarps, globose to linear in fruit; mericarps 3 or 6. x = 6. The fruit type of Triglochin has been variously denominated interpreted. We follow R. M. T. Dahlgren et al. (1985), who considered the fruits to be schizocarps with 1-seeded mericarps. Although Linnaeus, in his original publication of the name, treated Triglochin as neuter, botanical tradition in North America and elsewhere has generally assigned feminine gender (ICBN International Code of Botanical Nomenlature, Art. 62.1); for this reason and because the Greek word gGlochin (g l w c i n ) is feminine (ICBN, Art. 62.2), the feminine gender is the more correct under the Code and is adopted in the Flora. The use of the neuter gender in some recent works appears to reflect a pre-1987 wording of the Code that was held to require adoption of the gender assigned by the original author.