87 
ulate, longer than the tube: pod oblong, 6-seeded.—In Gillespie and Comal Coun- 
ties, and probably general between the Colorado and the Rio Grande. 
5. V. Ludoviciana Nutt. Glabrous (except the young shoots): stem rather stont, 
6 to 9 dm. long, strongly angled and climbing: leaflets 5 to 6 pairs, elliptical or obo- 
vate, obtuse or emarginate, 12 to 16™™ long; stipules subulate, very small: pedun- 
cles 2 to 6-flowered, at length longer than the leaves: calyx-teeth broad, acuminate, 
shorter than the tube: pod broadly saber-shaped, glabrous, 5 or 6-seeded.—Through 
eastern and southern Texas to Pt. Isabel, and as far west as San Antonio. 
29. LATHYRUS Tourn. (VercHiinc. EVERLASTING PEA.) 
Mostly smooth plants, like Vicia except that the style is somewhat 
dilated and flattened upwards and is bearded down the inner face.— 
Our species have the leaves tendril-bearing, the peduncles equaling or 
exceeding the leaves, and the pods sessile. 
1. L. pusillus Ell. Annual, glabrous: stem winged: leaflets 2, narrow: racemes 
1 or 2-flowered: flowers small, purple: pod linear: seeds minutely tuberculate.—A 
species of the Gulf States extending into Texas. 
2, L. palustris L. Perennial, glabrous or somewhat pubescent: stem often 
winged: leatlets 4 to 8, narrowly oblong to linear, acute, 2.5 to 5 em. long ; stipules 
mostly narrow, often small: peduncles 2 to 6-flowered: flowers purple, 12 mm. long.— 
2 
Var. ANGUSTIFOLIUS Watson has elongated, narrow and grass-like leaflets, and 
smaller stipules.—Extreme western Texas and adjacent New Mexico. 
30. APIOS Boerhaave. (GrouND-NUT. WILD BEAN. ) 
A perennial herb, twining and climbing over bushes, bearing edible 
tubers on underground shoots, pinnately 3 to 7-foliolate leaves, ovate- 
lanceolate leaflets, flowers in dense and short often branching racemes, 
a strongly incurved and at length coiled keel, and a straight or slightly 
curved linear elongated thickish many-seeded pod. 
|. A. tuberosa Mench. Flowers brown-purple or chocolate-color, violet-scent- 
ed.—An eastern species, extending into Texas to Gillespie and Wilson Counties, 
31. CENTROSEMA DC. (SrurRED BUTTERFLY-PEA.) 
Twining perennials, with 3-foliolate Stipellate leaves, large showy 
flowers, striated stipules, bracts and bractlets (the latter longer than 
the calyx), a short 5-cleft calyx, the standard spurred at base, a broad 
and merely incurved keel, style minutely bearded next the stigma, and 
a long linear flat pod pointed with the awl-shaped style, many-seeded 
and thickened at the edges. 
1, C. Virginiaum Benth. Rather rough with minute hairs: leaflets varying 
from oblong-ovate to lanceolate and linear, very veiny, shining: peduncles 1 to 4- 
flowered: calyx-teeth linear-awl-shaped: corolla violet, 2.5 cm. long: pod straight, 
10 to 12.5 cm. long.—A species of the Southern States extending into Texas and 
down the coast to Brazos Santiago. 
32. CLITORIA L. (BUTTERFLY-PEA. ) 
Ereet or twining perennials, with mostly pinnately 3 foliolate stipel- 
late leaves, very large flowers on 1 to 3-flowered peduncles, opposite 
striate bractlets, a tubular 5-lobed calyx, erect and spurless standard, 
