FABACEAE 631 
12. Petalostemon Sabinalis S. Wats. Plant glabrous, yellowish green. Stems 
branched at the base, the branches ascending, 2-4 dm. long, commonly simple: leaflets 
11-15, the blades linear or slightly broadened upward, 10-15 mm. long, nearly flat, gland- 
ular-dotted beneath, blunt: spikes cylindric, 4-6 em. long, about 1 cm. thick, excluding 
the corollas, peduncled : bracts about as long as the calyxes, deciduous: calyx glabrous 
without, about 3 mm. long; tube ribbed at maturity ; lobes triangular, shorter than the 
tube: corolla rose-colored ; standard notched at the apex, the other petals obtuse. 
On dry plains or prairies, Texas. Spring and summer. 
13. Petalostemon purpüreus (Vent.) Rydb. Plant glabrous or sparingly pubes- 
cent. Stems often tufted, erect or ascending, 3-9 dm. tall, more or less branched above : 
leaflets 3-5, the blades narrowly linear, 8-20 mm. long, acute, strongly involute : spikes 
oval to cylindric, 1.5-5 cm. long: bracts oblanceolate, abruptly acuminate : calyx silky, 
usually surpassing the bract ; tube campanulate ; lobes triangular, much shorter than the 
tube : corolla violet or purple ; standard with a dilated blade cordate or subcordate at the 
base. [Petalostemon violaceus Michx. ] 
On prairies, Northwest Territory to Minnesota, Indiana, Texas and Colorado. Summer. 
14. Petalostemon Porterlàànus Small. Plant sparingly pubescent, but the upper 
arts, at least, tawny-pubescent. Stems 2-3 dm. tall, or sometimes taller, more or less 
ranched : leaflets 3-5, the blades nearly linear, 8-14 mm. long, strongly involute: spikes 
oblong or cylindric, 1.5-2 em. long: bracts surpassing the buds : calyx villous ; tube promi- 
nently ribbed ; lobes shorter than the tube : corolla violet-purple. 
On prairies, Arkansas. Summer. 
15. Petalostemon tenuifdlius A. Gray. Plant somewhat pubescent. Stems usually 
branched at the base, with erect or ascending branches, 1.5-3 dm. tall, pale: leaflets 3-5, 
the blades linear to linear-spatulate, 8-18 mm. long, involute, blunt, sparingly glandular : 
spikes cylindric, 2-4 cm. long, barely 1 cm. thick: bracts rather abruptly contracted into 
slender subulate tips: calyx silky-villous like the bracts, becoming about 4 mm. long: 
lobes triangular-lanceolate, about as long as the tube: petals rose-colored ; standard with 
a cordate hooded blade. 
On plains or prairies, Arkansas to Arizona. Summer. 
16. Petalostemon Gattingeri Heller. Plant sparingly pilose or glabrous below. 
Stems usually several together, 2-5 dm. long, ascending or decumbent, simple or much 
branched : leaflets 5-7, the blades narrowly linear or linear-oblong, 1-2 cm. long, glandu- 
lar, slender at the base: spikes cylindric, 3-10 cm. long: bract oval-lanceolate with snb- 
ulate tips, pubescent : calyx villous-pilose, shorter than the bract; tube campanulate, 
ribbed ; lobes lanceolate or triangular-lanceolate, acute: corolla rose-purple; standard 
with a broad blade truncate or cordate at the base. 
On rocky barrens and in cedar glades, Tennessee. Spring and summer. 
17. Petalostemon Reverchdnii S. Wats. Plant bright green. Stems branched 
at the base, the branches more or less diffuse, 1-2 dm. long, finely pubescent : leaflets 
glabrous, 5-11, the blades linear or linear-oblanceolate, 7-10 mm. long, acutish, somewhat 
involute: spikes subglobose or oblong-globose, 1-1.5 cm. long, becoming 4-7 cm. long at 
maturity, about 1 em. thick: rachis tomentulose: bracts mostly shorter than the calyxes, 
eciduous : calyx about 4 mm. long, silky-villous ; lobes acute or acuminate: corolla red 
or deep pink. : 
On the summit of Comanche Peak, Texas. Spring and summer. 
18. Petalostemon pubéscens (A. Gray) Heller. Plant glaucous. Stems usually 
MM together, erect or ascending, 3-7 dm. tall, simple or nearly so: leaflets 3-7, the 
obl es linear, 10-14 mm. long, acute, glandular beneath, involute, slender-stalked : spikes 
b ong or oval, 2-4 cm. long: bracts broadly ovate, short-tipped : calyx surpassing the 
— tube campanulate, glabrate ; lobes triangular-lanceolate, acuminate, silvery pubes- 
cent: corolla rose-purple ; standard with a cordate or subcordate blade. 
In dry soil, Texas. Spring and summer. 
uu Petalostemon Stanfiéldii Small. Plant glabrous to the inflorescence. Stems 
gas -3 dm. tall, often branched near the base, the peduncles or most of them slightly 
mh 3B as the leafy stem: leaflets 3-5, the blades linear or narrowly linear-spatu- 
pe. s 2 mm. long, acute, strongly involute: spikes cylindric or oblong-cylindric, 1-2.5 
i ong, less than 1 cm. thick: calyx puberulent; lobes triangular, about one-half as 
ng as the tube: corolla rose-purple ; standard with a broad cordate or subcordate blade. 
On plains or prairies, Texas. Summer. 
Pe 20. Petalostemon ténuis (Coulter) Heller. Plant nearly glabrous below the in- 
escence. Stems 3-4 dm. tall, relatively slender, somewhat glaucous, branched : leaf- 
