This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol2", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
Herbs or low shrubs, with evenly pinnate leaves, often sensitive to the touch, mostly persistent strongly nerved stipules, and yellow flowers in small axillary clusters or solitary in the axils. Calyx-lobes acuminate. Corolla somewhat irregular, three of the five petals smaller than the others. Stamens 10, all usually with perfect anthers opening by terminal pores. Pods linear, flat, more or less elastically dehiscent, the valves twisting. [Greek, low crest.]
About 100 species, widely distributed in temperate and tropical regions. Besides the following, some 15 others occur in the southern United States. Type species: Chamaecrista nictitans (L.) Moench.
Flowers 2"-4" wide, short-pedicelled.
Flowers 1'-1 1/2' wide, slender-pedicelled.
Cassia nictitans L. Sp. Pl. 380. 1753. Chamaecrista nictitans Moench, Meth. 272. 1794.
Annual, erect or decumbent, branching, more or less pubescent, 6'-15' high. Stipules subulate-linear, persistent; leaves petioled, sensitive, bearing a small gland near the base of the petiole; leaflets 12-44, linear-oblong, obtuse and mucronate at the apex, rounded and oblique at the base, inequilateral, 3"-8" long, 1"-1 1/2" wide; flowers 2-3 together in the axils, short-pedicelled, 2"-4" broad; calyx-lobes acute or acuminate; stamens 5, all perfect; pod linear, nearly glabrous, or pubescent, 1'-l 1/2' long, 2'-2 1/2' wide.
In dry soil, Maine to Georgia, west to Indiana, Kansas and Texas. Also in the West Indies. July-Oct.
Cassia fasciculata Michx. Fl. Bor. Am. 1: 262.
1803. Cassia Chamaecrista robusta Pollard, Mem. Torr.
1897. C. fasciculata Greene; Pollard in Small, Fl. SE.
U. S. 587. 1903.
Annual, erect or spreading, widely branched, pubescent, with spreading hairs, or nearly glabrous, 1°-2 1/2° high. Stipules subulate-linear, persistent; leaves petioled, with a sessile gland on the petiole, sensitive; flowers 2-4 together in the axils, 1'- 11/2' broad, slender-pedicelled, showy, some of the petals often purple spotted; leaflets 20-30, linear-oblong or the upper lanceolate, obtuse, mucronate, inequilateral, oblique at the base, 4"-10" long, 1 1/2"-2" wide; calyx-lobes long-acuminate; stamens 10, all perfect, 4 of the anthers yellow, 6 purple; pod linear, pubescent or glabrate, 1 1/2'-2 1/2' long, 2 -3 wide.
Chamaecrista depréssa (Pollard) Greene, of the Gulf States, which is apparently perennial, with fewer leaflets, is recorded from Missouri. It is probably identical with C. chamaecristoides (Collad.) Greene, of the same region.