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10 Nelson : New Plants from Wyoming 



varicate or reflcxed (probably all ultimately reflexed): ovules 

 rcniform, rather large, nearly filling the pod. 



This in habit suggests A. jioiccits Gray," but possibly it is more 

 closely allied to A. Coltoni Jones. Its j unciform stems and leaves 

 are very characteristic. So far I have found this species in but 

 one jocality, viz., near Point of Rocks, Sweetwater Co., where it is 

 an occasional plant on sandy, stony slopes. First secured in 

 1897, no. 3081 and again, 1898, no. 4839. It comes into blos- 

 som early in June. 



I 



Astragalus exilifolius . 



An acaulescent perennial from large, deep-set roots ; caudex 

 multicipital, closely caespitose : leaves densely crowded on the 

 crown, simple, narrowly linear, the petiole-like base almost fili- 

 form, 2-4 cm. long, pungently acute, sparsely short hirsute, the 

 dead leaves persisting for a time on the branches of the caudex : 

 stipules scarious, ovate, imbricated, the largest 5 mm. long : pe- 

 duncles about equaling the leaves, 1-2-flowered ; pedicels short, 

 bracts small, scarious : calyx campanulate, glabrous, or nearly so, 

 its lobes subulate, shorter than the 3-4 mm. long tube: corolla 

 showy, 15-20 mm. long, white, the keel tipped with purple : pod 

 sessile, I -celled, oblong, slightly curved with an acuminate apex, 

 purple mottled, 12-15 ^^- long, both sutures prominent, the ven- 

 tral sharply keeled; seeds few (1-4). 



This adds one more member to the section in which A, spatii- 

 latiis Shcld. and A siniplicifoUiis Wats, are the conspicuous mem- 

 bers. The characters of this separate it more sharply from both 

 of those than they are separated from each other. 



It is of the desert region of south-central Wyoming, occurring 

 as rounded tufts on the barren clay ridges of the Cretaceous forma- 

 tion. Type specimen, no. 4493, by Mr. Elias Nelson, Freezeout 

 Hills, Carbon County, July 10, 1898. Collected also in the Rat- 

 tlesnake Hills, no. 4996. 



Astragalus aculeatus 



Perennial, the stout woody caudex bearing numerous, slender, 

 appressed-caespitose branches, hardly rising above the surface of 

 the soil, the mats from one to several decimeters in diameter : 

 leaves numerous, crowded on the short stems the bases of which 



i 



are covered with the persistent dead ones : leaflets 5-7, linear- 

 oblong, plane, involute or somewhat channelled, pungently long 

 mucronate, about 8 mm. long, green but under a lens sparsely 



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