[Rhynchosia Lour. Fl. Cochin. 562. 1793.]

Perennial twining, trailing or erect herbs, with pinnately 1-3-foliolate leaves, and yellow mostly axillary and racemose flowers. Leaflets generally punctate with resinous dots, not stipellate. Calyx 4-5-lobed, somewhat 2-lipped. Standard obovate or orbicular, spreading or reflexed. Wings narrow. Keel incurved at the apex or falcate. Stamens diadelphous (9 and 1). Ovary nearly sessile; ovules 2, rarely 1; style filiform. Pod flat, oblong or obliquely orbicular, 2-valved, 1-2-seeded. [Name diminutive of Dolichos.]

About 200 species, natives of warm and temperate regions. In addition to the following, some 12 others occur in the southern States. Type species: Dolicholus minimus (L.) Medic.

Leaflets 3.

Stem twining or trailing.

Racemes shorter than the leaves; flowers 3"-4" long.

1.

D. tomentosus.

Racemes longer than the leaves; flowers about 6" long.

2.

D. latifolius.

Stem erect, 1°-2 1/2° high.

3.

D. erectus.

Leaflets solitary , very broad; plants low, 3'-9' high.

4.

D. simplicifolius.

47 Dol cholus Medic Vorles Chur Phys Gesell 2 354  984

I. Dolicholus Tomentòsus (L.) Vail. Twining Dolicholus

Fig. 2642

Glycine tomentosa L. Sp. Pl. 754. 1753.

Rhynchosia tomentosa var. volubilis T. & G. Fl. N. A. 1: 285. 1838.

Rhynchosia tomentosa H. & A. Comp. Bot. Mag. I: 23 1835.

D. tomentosus Vail, Bull. Torr. Club 26: 112. 1899.

Trailing or twining, more or less pubescent with spreading hairs, simple or branched, 1°-3° long. Stipules ovate, acute, 2"-4" long, sometimes wanting; petioles shorter than the leaves; leaflets 3, or the lowest leaves I-foliolate, ovate, orbicular or broader than long, obtuse but generally pointed, 1'-2' long; racemes short-peduncled or sessile, 2-8-flowered; flowers 3"-4" long; calyx deeply 4-parted, the upper lobe 2-cleft; pod oblong, acute, pubescent, 8"-9" long, about 3" wide.

In dry sandy soil, Virginia to Florida, west to Texas. May-July.

2. Dolicholus Latifòlius (Nutt.) Vail. Prairie Rhynchosia

Fig. 2643

Rhynchosia latifolia Nutt.; T. & G. Fl. N. A 1. 285. 1838.

Dolicholus latifolius Vail, Bull. Torr. Club 26: 114. 1899.

Softly pubescent, stem angled, trailing or climbing, sometimes 50 long, with a few long branches. Stipules lanceolate, small, or wanting; petioles 1'-3' long; leaflets 3, broadly ovate, or somewhat rhomboid, or the end one orbicular, 1'-3' long, mostly obtuse; racemes elongated, exceeding the leaves, sometimes 1 ° long in fruit, many-flowered; pedicels 1"-2" long; calyx about 6" long, very deeply parted, the segments narrowly lanceolate, acuminate; corolla little longer than the calyx; pod oblong, acute, very pubescent, about 1' long.

In dry soil, Missouri to Louisiana and Texas. May-June.

2 Dolicholus Latif Lius Nutt Vail Prairie Rhynchos 9852 Dolicholus Latif Lius Nutt Vail Prairie Rhynchos 986

3. Dolicholus Eréctus (Walt.) Vail. Erect Rhynchosia

Fig. 2644

Trifolium erectum Walt. Fl. Car. 184. 1788.

Rhynchosia erecta DC. Prodr. 2: 384. 1825.

Rhynchosia tomentosa var. erecta T. & G. Fl. N. A. 1: 285. 1838.

D. erectus Vail, Bull. Torr. Club 26: 115. 1899.

Erect, rather stout, simple or slightly branched, velvety-pubescent or tomentose, 1°-2 1/2° high. Stipules linear-lanceolate, acuminate, 2"-3" long; petioles shorter than or equalling the leaves; leaflets 3, oval, ovate or slightly obovate, thick, densely tomentose, especially beneath, obtuse or acute, 1-2' long; racemes 5-15-flowered, sessile or short-peduncled; flowers 3"-5" long; pod oblong, pubescent, 6's" long, about 3" wide.

In dry soil, Delaware to Florida, Tennessee and Louisiana. May-Sept.

4. Dolicholus Simplicifòlius (Walt.) Vail. Round-Leaved Rhynchosia

Fig. 2645

Trifolium simplicifolium Walt. Fl. Car. 184. 1788. Rhynchosia renifortnis DC. Prodr. 2: 384. 1825.

Rhynchosia tomentosa var. monophylla T. & G. Fl. N. A. 1: 284. 1838.

Rhynchosia simplicifolia Wood, Bot. & Fl. 96. 1870.

D. simplicifolius Vail, Bull. Torr. Club 26: 114. 1899.

Erect, low, simple, pubescent with spreading hairs, 3'-9' high. Stipules lanceolate, acuminate, 3"-4" long; petioles shorter than or exceeding the leaves; leaflet usually solitary, orbicular or broader, thick, obtuse and rounded or apiculate at the apex, slightly cordate at the base, 1'-2' long (leaflets rarely 3, the lateral ones ovate); racemes rather densely flowered, short-peduncled or sessile; flowers 3"-5" long; pod as in the preceding species.

In dry soil, Virginia to Florida, Tennessee and Louisiana. May-July.

4 Dolicholus Simplicif Lius Walt Vail Round Leaved 987