Protologue Description: BIDENS CONNATA Muhl., var. gracilipes, n. var., foliis primariis labatis, lobis 2-4 basilaribus divergentibus decurrentibus, lobo terminali foliisque superioribus lanceolato-attenuatis anguste serratis dentibus subfalcatis, petiolis gracilibus vix marginatis; achaeniis exterioribus 3-4 mm. longis, interioribus 4.5-5 mm. longis aristis marginalibus 2-2.5 mm. longis.
Primary leaves lobed, the 2-4 lobes basal, divergent, decurrent; the terminal lobe and the upper leaves lance-attenuate, slenderly serrate with subfalcate teeth; petioles slender, scarcely margined: outer achenes 3-4 mm. long; the inner 4.5-5 mm. long, with marginal awns 2-2.5 mm. long.- MASSACHUSETTS: peaty margins of small ponds west of White Pond, Chatham, September 9, 1913, Fernald & Long, no. 10,683; quagmire in woods south of Sparrow Young's Pond, Chatham, August 20, 1918, Fernald & Long, no. 17,606; borders of peaty quagmires east of Buck Pond, Harwich, August 30, 1918, Fernald & long, no. 17,607; sandy beach of Seymour Pond, Harwich, September 19, 1918, Fernald & Weatherby, no. 17,608 (TYPE in Gray herb.); wet shore, Mashpee Pond, Mashpee, September 16, 1916, Bean, Bird & Knowlton.