239 



OCREATI. 23. 



Perennials with densely tufted short stems with con- 

 gested internodes or the upper ones elongated but much 

 shorter than the leaves, branched below, ascending to 

 erect, from a woody root, rarely 3 dm. long. Stipules 

 sheathing but rather small. Leaves narrow, all petioled, 

 1-3 dm. long, the rachis at least as long as petiole and 

 slender. Leaflets 5-8 pairs, narrow to oblong, mostly acute 

 and folded, not acicular, not contiguous, 2-3 cm. long, 

 long-petiolulate and jointed to petiole. Flowers spicate 

 or in fruit a little racemose, about sessile, 6-12 mm. long, 

 neither reflexed nor stubby, with cylindrical to long-cam- 

 panulate tube which is 3-5 mm. long and mostly a trifle 

 longer than the subulate teeth. Bracts elongated and 

 conspicuous, triangular-subulate. Pods conspicuously ob- 

 compressed, inclined to be sulcate above and below, oval 

 to oblong, abruptly apiculate, not much exserted from 

 the calyx, coriaceous and variously corrugated, the sides 

 rounded, cross section variously reniform or like the 

 figure 8 but not at all 2-celled nor with sutures produced 

 within, mostly a little oblique at tip but not arched, very 

 slightly if at all inflated. Ventral suture raised exter 

 nally and very much thickened or prominent, pod when 

 sulcate ventrally is so on each side of suture. Plants 

 of the arid deserts mostly in alkaline and very poor 

 clay soil, but not in sinks or where water stands. Pu- 

 bescent with closely appressed hairs. Plants blooming in 

 early summer. 



KEY. 



A. Pubescence attached by the middle or near it (by the base iim 

 A. argillcsus), of flat and tapering hairs. Stems densely tufted 

 and decumbent, slender, at least 1 dm. long when fully devel- 

 oped, hoary. Leaflets linear, about 2.5 cm. long. Flowers 

 densely spicate, about 1 cm. long. Bracts about as long as 

 calyx and its lobes. Pods splitting the calyx at maturity, shal- 

 low-sulcate at both sutures. 

 AB. Pods hoary, about equaling the calyx teeth, ovate to oval, 

 straight but tip rarely a little curved, rounded at base, mostly 

 acute, obcompressed at least at base and mostly sulcate, 

 with ventral suture prominent, loosely spicate. Flowers white 

 to yellowish, about 12 mm. long. Calyx short, campanulate; 

 teeth subulate, about as long as tube. Leaves 1-1.3 dm. long. 

 Leaflets 2-5 mm. wide, 2.5 cm. long, 4-7 pairs. Stipules hya- 

 line, broad, about 7 mm. long. Stems flexuous, some inter- 

 nodes 8 cm. long, perennials. Whole plant erect or ascending 

 1.5-3 dm. long. Pubescence closely appressed throughout, 

 hoary except the pods rarely. Plants with a strong snake- 

 like odor. 



Peduncles very short or none. 200 sophoroides. 



Peduncles at least as long as leaves. 201 confertiflorus. 



