136 LEAFLETS. 



la between the habi tat of this and that of .S. affinis are bar- 

 riers of high mountain and low desert in untold number ; and 

 other well differentiated species of this genus will be found in 

 that significant and varied interval. 



S. cissoDBS. Dwarf, with tortuous or even reclining branches 

 glabrous and of a light ash-gray, the growing twigs almost fili- 

 form, puberulent : foliage small, ivy -green, veiny and glabrous 

 above, paler beneath and appressed-pubescent along the veins 

 only, the leaves all simple, often deeply trisected in imitation 

 of the trifoliolate, even occasionally divided to the midvein ■ 

 terminal segment broader than long, incisely 3-lobed, the margin 

 angular-toothed; lateral lobes about half as large, not lobed but 

 coarsely dentate. 



Grand Canon of the Colorado, Ariz., near Indian Garden, 

 Bright Angel Trail, C. H. Merriam, 10 May, 1903. Elegant 

 vine-like species, and a nice link between the usual trifoliolate 

 type, and that with rounded and simple leaf. 



S. ANisoPHTLLA. Dwarf, stout rigid short-branched desert 

 shrub ; twigs for two seasons puberulent, afterwards gray, 

 glabrate : foliage at least half -grown at flowering time, small, 

 distinctly trifoliolate but lateral leaflets small and degenerate, 

 never equal to each other in size, the largest not half the size of 

 the terminal, this obovate-cuneiform, lightly 3-lobed and obtusely 

 so : small round capitif orm spikes many ; bracts transverse- 

 rugose in the middle, only minutely and obscurely ciliolate. 



Surprise Canon, Panamint Mountains, southeastern Calif. 

 A. K. Fisher in Death Valley Exp. n. 618 as in U. S. Herb. A 

 still earlier link in the connection between trifoliolate and sim- 

 ple-leaved species. 



S. ELBGANTULA. Slender and tortuous or reclining like 

 S. cissodes, only the growing twigs puberulent, also the foliage 

 half -grown at flowering time : leaflets 3 and subequal, all incisely 

 lobed, the terminal one doubly so : spikes 1 or 3 at the end of 

 each slender branch, capitiform, broader than long; bracts 

 tomentulose. 



Flagstaff, Arizona, May, 1893, N. C. Wilson, as in my herba- 

 rium. 



