[*] Flowers imperfectly papilionaceous, perfect. Trees.

40. Cercis. Calyx campanulate, 5-toothed. Pod flat, wing-margined. Leaves simple.

[*][*] Flowers not at all papilionaceous, perfect. Calyx 5-parted. Herbs.

41. Cassia. Leaves simply and abruptly pinnate, not glandular-punctate.

42. Hoffmanseggia. Leaves bipinnate, glandular-punctate.

[*][*][*] Flowers not at all papilionaceous, polygamous or diœcious. Trees.

43. Gymnocladus. Leaves all doubly pinnate. Calyx-tube elongated, at its summit bearing 5 petals resembling the calyx lobes. Stamens 10.

44. Gleditschia. Thorny; leaves simply and doubly pinnate. Calyx tube short; its lobes, petals, and the stamens 3–5.

Suborder III. Mimoseæ. (Mimosa Family.) Flower regular, small. Corolla valvate in æstivation, often united into a 4–5-lobed cup, hypogynous, as are the (often very numerous) exserted stamens. Embryo straight. Leaves twice pinnate.

45. Desmanthus. Petals distinct. Stamens 5 or 10. Pod smooth.