58 LEGUMINOS^E. (PULSE FAMILY.) 



conspicuous, ovate, pubescent, deciduous : calyx very villous, with long slender 

 teeth. — From Colorado to S. Arizona and eastward to the Mississippi from 

 Texas to Illinois. 



2. D. laxiflora, Pursh. Erect, 3 to 4 feet high : branches slender and 

 spreading : leaflets 4 to 5 pairs, linear-oblong : spikes panicled, few-flowered : 

 flowers distant, white : bracts very broad, almost orbicular, glandular, coriaceous, 

 glabrous, slightly cuspidate : calyx-teeth beautifully plumose. — From Colorado 

 to the plains of the Missouri, and southeastward to Arkansas and Texas. 



3. D. formosa, Torr. Suffruticose, much branched : leaflets very small, 

 about 5 pairs, cuneate-oblong, retuse, dotted with black glands beneath : spikes loose, 

 few-flowered, on short peduncles : flowers large and showy, bright purple : bracts 

 ovate, silky-villous on the margin. — On the Platte (James), and southward. 



* * Not glabrous: flowers yellow (deep purple in No. 7). 

 ■>- Leaves palmately trifoliolaie, not dotted. 



4. D. Jamesii, Torr. & Gray. Stems several from one root, 4 to 9 inches 

 high, somewhat woody at base : whole plant silky-pubescent : leaflets obovate, 

 very obtuse : spikes oblong, sessile, dense and broad ; bracts ovate, acuminate, 

 villous. — S. Colorado and southeastward. 



h- +- Leaves pinnately compound, with 2 to 6 pairs of leaflets. 



5. D. aurea, Nutt. Stem pubescent, erect, 2 feet high : leaflets 3 to 4 

 pairs, oblong-obovate and linear-oblong, more or less silky-pubescent : spikes ovate, 

 very compact, on long peduncles : bracts rhombic-ovate, as long as the calyx. 

 — On the plains from the Missouri River to Texas. 



6. D. rubeseens, Watson. Like the last but more slender, the leaves tri- 

 foliolate, and the flowers smaller, the yellow petals becoming purplish. — Proc. 

 Am. Acn.d. xvii. 369. D. nana, Torr., var. elutior, Gray. S. E. Colorado, 

 southward and eastward. 



7. D. lanata, Spreng. Decumbent, canescently tomentose throughout: the 

 stems 1 to 3 feet long : leaflets 4 to 6 pairs, obovate-cuneate, emarginate : spikes 

 usually opposite the leaves. — From Nebraska, Arkansas, and Indian Territory 

 to Texas, New Mexico, S. Colorado, and Utah. 



8. PETALOSTEMOlf, Michx. Pkairie Clover. 



Similar to the last, but with only 5 stamens and the flowers always in dense 

 bracteate cylindrical spikes. 



* Smooth or nearly so : leaflets 5 to 9 : spikes globose to cylindrical. 



1. P. Violaceus, Michx. Leaflets 5, narrowly linear: spikes globose- 

 ovate, or oblong-cylindrical when old : bracts pointed, not longer than the silky- 

 hoary calyx : corolla rose-pnrple. — Prairies from the Saskatchewan to Texas, 

 and from Colorado to Indiana. 



2. P. candidus, Michx. Leaflets 7 to 9, lanceolate or linear-oblong : spikes 

 oblong, cylindrical when old : bracts awned, longer than the nearly glabrous 

 calyx: corolla white. — With the last. 



3. P. macrostaehyus, Torr. Leaflets 5 to 7, lanceolate-oblong, obtuse, 

 dotted beneath: spikes cylindrical, elongated: bracts as long as the flower; 

 calyx silky-villous : corolla nearly white. — From Colorado to Oregon. 



