37 



FABACEAE. 



Vol. II. 



4. Petalostemum multiflorum Nutt. Round- 

 headed I'rairie-ckjver. Fig. 2515. 



P. mulliflorus Nutt. Journ. Phil. Acad, 7: 92. 18.34. 



Kuhnistera muUiflora Heller, Mem. Torr. Club 5; ly;. 

 1894. 



Glabrous, erect, corymbosely much branched, i-2 

 high. Leaves short-petioled, often clustered; leaflets 

 3-9, linear or somewhat oblanceolate, obtuse or ob- 

 tusish at the apex, cuncate or narrowed at the base, 

 short-stalked, 4"-6" long, l"-\" wide; peduncles 

 elongated; heads globose, 4"-6" in diameter; bracts 

 subulate, shorter than the calyx ; calyx-teeth slightly 

 pubescent; corolla white, about 2" long; wings and 

 keel-petals ovate, oval, or slightly cordate. 



Plains, western Iowa to Missouri, Kansas, Arkansas 

 and Texas. Summer. 



5. Petalostemum purpureum (Vent.) Rydb. 

 A'iolet or Purple Prairie-clover. '\g. 2516. 



Daica purpurea Vent. Hort. Cels. pi. 40. 1800. 

 Petalostcmoii z'iolaccuin Miclix. FI. Bor. Am. 2 : 50. 1803. 

 Dalca violacea Willd. Sp. PI. 3 : 1337. 1803. 

 Kuhnistera purpurea MacM. Met. Minn. 329. 1892. 

 P. purpureum Rydb. Mem. N. Y. Bot. Gard. i : 238. 1900. 



Glabrous or slightly pubescent, erect, ii-3 high, 

 branching above. Leaves short-petioled, more or less 

 clustered ; leaflets 3-5, narrowly linear, 3"-9" long, 

 i"-i" wide, acutish and often mucronate at the apex, 

 narrowed at the base, very short-stalked ; spikes pe- 

 duncled, oblong, or finally cylindric, -2' long, about 

 5" thick ; bracts obovate, mucronate, nearly glabrous, 

 equalling the silkj'-pubescent calyx or shorter ; corolla 

 violet or purple, about 2" long ; standard cordate ; 

 wings and keel-petals oblong. 



Prairies and plains, Indiana to Manitoba. Saskatche- 

 wan, Texas and Colorado. Often grows with P. can- 

 didum. July-Aug. Thimbleweed. Red tassel-flower. 



6. Petalostemumtenuifolium A. Gray. Silky 

 Prairie-clover. Fig. 2517. 



P. tcnuifolius A. Gray. Proc. Am. Acad. 11 : 73. 1876. 

 Kuhnistera tenuifolia Kuntze. Rev. Gen. PI. 192. 1891. 



More or less pubescent, erect, branching, i-2 

 high. Leaves short-petioled ; leaflets 3-5, linear, ob- 

 tuse, somewhat involute, dotted with sessile glands, 

 3"_5" long, i"-i" wide, very short-stalked or sessile; 

 peduncles terminal, elongated, bracted; spikes ob- 

 long or cylindric, V-iV long, about 5" thick, the 

 rachis pubescent; flowers rose-purple, about 2*" 

 long; bracts ovate, aristate, silky-pubescent, slightly 

 exceeding the very silky-pubescent calyx; standard 

 nearly orbicular, cordate, cucullate. 



In dry soil, Kansas and Arkansas to New Mexico. 

 luly-Aug. 



