128 Sparsiflori. 



SPARSIFLORI. 5. 



Pods chartaceous, reticulated, lunate, sulcate dorsally 

 with ventral suture concave or rarely straight, tip straight or 

 ascending nearly m line with the ventral suture, but '.vhich is 

 humped a little at the end, acute at both ends or short-stipitate, 

 not splitting the calyx, cross section normally triquetrous, pod 

 laterally' flattened, a little inflated, with tip flat and triangular- 

 acute, length normally 1-3 cm. but sparsiflorus is shorter. 

 Flowers light-colored, mostly capitate, rarely short-racemose, 

 rel'lexed or widely spreading, 5-10 mm. long, with campanulate 

 calyx tube 1-3 mm. long. Banner oval, arched abruptly at 

 (below only in A. villosus) or beyond calyx tips to 45 to 90 

 degrees, with sides reflexed below, notched, 3-6 mm. long, 

 nearlj' tAvice as long as keel. Wings narrowly oblong, obtuse, 

 about 1-2 mm. wide, narroAver than keel and arched somewhat. 

 Keel straight below, abruptly arched at tip to erect and tip tri- 

 angular and 2-3 mm. high and rounded to acutish and dark 

 or colored. Bracts small, or narrow. Pedicels slender. Pedun- 

 cles longer than the leaves except in typical sparsiflorus when 

 fully mature, axillary nearly throughout, slender. Middle 

 leaves 5-12 cm. long, about three times the internodes, the low- 

 est leaves very much reduced. Petioles short above, leaf rachis 

 long and filiform. Leaflets rather long-petiolulate, flat, 

 rather distant, narrowly-elliptical to obcordate, rounded to re- 

 tuse, not over 1 cm. long, 4-12 pairs. Stipules 2-4 mm. long 

 except in villosus, greenish. Stems filiform or njarly so and 

 prostrate or straggling, 2-7 dm. long, forniiutr mostly open 

 mats from a single crown terminating an erect and slender 

 root. Plants perennial. Pubescence attached b}^ the base and 

 often loose. 



KEY 



A. prostrate plants. Pods reticulated, chartaceous, ascending, wider 

 above, with cross-section triangular-cordate and with dorsal suture 

 a mere line within, and the ventral suture not intruded but merely 

 a sharp and raised line. Calyx teeth as long as the tube. Leaflets 

 oval to obcordate. Flowers reflexed in oblong spikes. Leaves 

 nearly sessile. 



Pubescence of soft, long, spreading hairs. 8i villosus. 



Pubescence none except on calyx. 82 obcordatus. 



2A. Plants weak and decumbent. Calyx teeth short. Flowers rather 

 few. Leaflets mostly narrow. Leaves all petioled. Pods charta- 

 ceous, mottled, with dorsal suture little intruded or not at all, 

 wider above, cross section ovate to triangular-cordate. Flowers 

 very few, hardly 5 mm. long, much arched, and rather scattered, 

 on peduncles shorter than the leaves. 



83 sparsiflorus 



