Genus 47. 



PEA FAMILY. 



421 



47. DOLICHOLUS Medic. Vorles. Chur. Phys. Gesell. 2 : 354. 1787. 



[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-S-lobed, somewhat 2-lipped. Standard obovate or orbicular, spreading 

 or reflexed. Wings narrow. Keel incurved at the apex or falcate. Stamens diadelphous 

 (pandi). Ovary nearly sessile; ovules 2, rarely i ; style filiform. Pod flat, oblong or obliquely 

 orbicular, 2-vaIved, 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 $"-4" long. 

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

 Stem erect, i°-2^° high. 

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



1. D. ionientosns. 



2. D. latifolius. 



3. D. erectus. 



4. D. siniplicifolius. 



I. Dolicholus tomentosus (L.) Vail. Twin- 

 ing Dolicholus. Fig. 2642. 



Glycine tomentosa L. Sp. PI. 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, i°-3° long. 

 Stipules ovate, acute, 2"-4" long, sometimes want- 

 ing ; 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-cIeft ; pod oblong, acute, 

 pubescent, &"-g" long, about 3" wide. 



In dry sandy soil, Virginia to Florida, west to 

 Texas. May-July. 



2. Dolicholus latifolius (Nutt.) Vail. 

 Prairie Rhynchosia. Fig. 2643. 



Rhynchosia latifoUa Nutt. ; T. & G. Fl. N. A i . 285. 

 1838. 



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

 1899. 



Softly pubescent, stem angled, trailing or climb- 

 ing, sometimes 5° long, with a few long branches. 

 Stipules lanceolate, small, or wanting; petioles 

 l'-3' long ; leaflets 3, broadly ovate, or somewhat 

 rhomboid, or the end one orbicular, i'-3' long, 

 mostly obtuse; racemes elongated, exceeding the 

 leaves, sometimes 1° long in fruit, many-flowered ; 

 pedicels i"-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 i' long. 



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

 June 



