Very much like no. 1 [Cardaria draba (L.) Desv.], and hybridizing with it, but the fr 2.5-6 נ4-6 mm, rounded to obovate or transversely elliptic, not or scarcely constricted at the septum, the base obtuse to rounded or subtruncate; 2n=48, 64, 80. Native to the Middle East, now intr. in N. Amer. in the same kinds of places as no. 1.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.