American featherfoil

Stems 3-5 dm. Leaves widely spaced proximally, becoming clustered to whorled near inflorescence; blade 1-8 cm. Inflorescences with inflated rachises (rays) and peduncle. Flowers: calyx 3-10 mm, longer than corolla; corolla white, 3-6 mm. Capsules 1.5-3 mm. Seeds 0.4-0.6 mm. 2n = 22.

Flowering summer. Pools, swamps, streams, quiet backwaters; 0-200 m; Ala., Ark., Conn., Del., Ga., Ill., Ind., Ky., La., Maine, Md., Mass., Miss., Mo., N.H., N.J., N.Y., N.C., Ohio, Okla., R.I., S.C., Tenn., Tex., Va., W.Va.

Hottonia inflata has been reported from Prince Edward Island (J. F. MacSwain and F. Bain 1891). It was most likely a casual waif; no specimens are known and it has not been seen there since. No specimens have been found to substantiate reports of H. inflata occurring in Florida. It is listed as threatened or endangered in some states and is believed to be extirpated in Pennsylvania, where it was last collected in 1931.