Podo-sclerocarpi. 143 



erect or less. Wings oblong to narrowly oblong, obli ;.ie 

 and rounded, scarcely arched, about 4 mm. longer than keel, 

 very thin. Keel 7 mm. long, straight, the tip abruptly arched 

 to erect and broadly deltoid and 3 mm. high. Calyx like 

 that of Toanus but rather narrower, slightly oblique at 

 tip, hyaline, sinuses rounded, teeth much shorter than tube. 

 Pedicels stout, in fruit 2-5 mm. long, in flov\.er very s' -rt 

 and about as long the subulate bracts. Peduncles arrjied, 

 rarely as long as the leaves, stout. Leaves about 2.5 .- i. 

 long, ascending, the middle ones the largest. Petioles al- 

 most none, angled. Leaves very wide and short. Leaflets 

 coarsely 1-nerved, about 3 pairs (rarely 10 pairs in pectina- 

 tus), 2.5-5 cm. long, linear when flat, almost filiform when 

 folded, rarely linear-oblanceolate, often alternate, arcuite, 

 acute, mostly not jointed to the short rachis. Stipules 

 green, reddish below, very long tipped. Stems sulcnte 

 strongly, nearly 2 ft. high, not tangled, moderately stout, 

 barely flexuous, with internodes shorter than the upper 

 leaves. Plants ashy-pubescent. Stipules conspicuous. Pub- 

 escence of broad and flat hairs attached by base and closely 

 appressed. Roots stout thick and erect. From the Green 

 river bad lands cf Wyoming to Kansas and northward in al- 

 kaline soil. Upperi part of Lower and lower part of Middle 

 Temperate life zones. 

 To is erect. 99 Grayi. 



Pods reflexed. loo pectinatus. 



AE2C. Pods opening most along the ventral suture except at tip 

 and mostly first at tip. Ventral suture either straight or con- 

 cave, never arched as much as the dorsal. Sutures not raised 

 in the green state, but evidently so in the dry. Pods in- 

 clined to be obcompressed, angled or winged when dry, strict- 

 ly 1-celled (the dorsal s'jture a trifle impressed in pterocar- 

 pus) conspicuously falcate, not inflated, ascending as well as 

 flowers. Stems rather zigzag and flexuous. Leaves narrow, 

 short-petioled, with several pairs of mostly straight leaflets. 

 Stipules small, not connate. 

 AB2CD. Pods with rounded sides, not all angled or winged, 

 purple or mottled, oblong-lanceolate and acuminate at tip 

 and shortly so at base, about 1 cm. wide. Flowers purple, 

 racemose, loose. Stems few in a place and inclined to be de- 

 cumbent. Growing in well drained gravelly sagebrush slopes 

 pr3ferably where there is a little alkali seep. 

 Pods narrow, nearly round in cross-section. loi Case!. 



AB2C2D. Pods when dry laterally winged and with wings 2 mm, 

 wide, sessile, erect (as well as the flowers except rarely 

 in A. pterocarpus), acute but not acuminate at tip, obtuse 

 but narrowed at base, very finely cross-veined, smooth, 3-4 

 cm. long, arcuate, with sutures narrow and not much thick- 

 ened. Flowers short-spicate. Calyx triangular-aftute at 

 base, the lower side straight, upper side a trifle arched, at- 

 tached on lower corner, hyaline. Terminal leaflet not jointed 

 to rachis, leaflets not early deciduous but attached by very 

 delicate petiolules, linear, rarely the lowest ones narrowly 

 oblong. Leaves not widely spreading. Densely tufted 

 stems slender and nearly straight, erect, freely branched 

 mostly, from woody root, succulent and very hard to dry. 

 Growing in low places. 

 Fods bio.id, much ohconipressed and 2-\vinged. 102 pterocarpus. 

 Tods narrow, not (lattened, 4-winged. 103 tetrapterus. 



