200 RANUNCULACEAE (BUTTERCUP FAMILY) 



Flowers very large, 2-3 cm. broad. 



Leaves 2-3-ternately parted into linear lobes . . lo. K. aapneus. 

 Leaves digitately 3-7-divided or parted . . . 17. R. eximius. 

 Plants of middle elevations or lower; mostly 2-4 dm. high. 



Wholly glabrous 18. R. eremogenes. 



More or less pubescent. 



Achenes with short hooked beak. 



1 1 is glabrous or nearly so; flowers small . . 19. R. Douglasii. 

 Stems hirsute; flowers 15-25 mm. broad. 



Pubescence mostly appressed . . . . 20. R. acriformis. 

 Pubescence mostly spreading . . . . 21. R. montanensis. 

 Achenes with straight stout beak. 



Stems stout, very rough hirsute; beak much shorter 



than the body of the achene. 

 Head of carpels oblong; petals not longer than 



the sepals 22. R. pennsylvanicus. 



Head of carpels globose or ovoid; petals longer 



than the sepals 23. R. Macounii. 



Stems slenderer; beak as long as the body of the 



achene ........ 24. R. maximus. 



1. Ranunculus Purshii Rich, in Frank. Journ. 751. 1823. Stems floating 

 or immersed, with the divisions of the leaves long and filiform; or rooting in 

 the mud and the leaves round-reniform and more or less deeply lobed and 

 toothed; petioles short, broadly stipulate-dilated at base: flowers large, the 

 petals with conspicuous obovate scales: achenes in a small globose head, 

 beaked by a short straight style. R. multifidus. Colorado and northward, 

 and across the continent. 



2. Ranunculus natans C. A. Meyer, in Ledeb. Ic. t. 114. 1829. Stem 

 filiform, creeping: leaves glabrous, petioled, reniform, 3-cleft; the lobes oval- 

 oblong, divaricate, the lateral ones sometimes somewhat 2-cleft: heads of 

 achenes globose, compact; style wanting. In swamps at middle elevations; 

 Colorado and northward. 



3. Ranunculus reptans L. Sp. PI. 549. 1753. Glabrous throughout: stems 

 filiform, creeping and rooting at the joints: leaves mostly lanceolate and acute 

 at each end: petals half longer than the sepals: achenes few in a small globular 

 head, plump; beak very short and curved. Found in Colorado, but most com- 

 mon northward, where it extends across the continent. 



4. Ranunculus calthaeflorus Greene, Erythea 3: 45. 1895. Nearly or 

 quite glabrous throughout: roots thickened-fibrous : stems usually solitary, 

 more or less branched, often dichotomously from near the middle, 1-3 dm. 

 high: leaves ovate and oblong-lanceolate, 3-10 cm. long, entire or nearly so; 

 the cauline somewhat narrower and sessile: inflorescence more or less corym- 

 bose: petals about 10, oblong-obovate or narrower: achenes in a sub globose 

 head; the beak short, subulate, and nearly straight. R. alismaefolius. (R. 

 unguiculatus Greene, Pitt. 4: 142. 1900.) Frequent at high altitudes in the 

 central Rocky Mountains. 



5. Ranunculus glaberrimus Hook. Fl. Bor. Am. 1: 13. t. 5. 1829. Gla- 

 brous, less than 1 dm. high: roots a fascicle of thickened fibers: stems 

 1 several-flowered: radical leaves elliptic, cuneate at base, 3-cleft to the 

 middle or deeper: flowers 18-25 mm. broad: petals twice as long as the 

 sepals, bright yellow, glossy and shining: achenes with a short beak. (R. 

 dlifitirus Oeene, Pitt. 2: 110. 1890.) -Colorado, northward and west to 

 Washington. 



0. Ranunculus Macauleyi Gray, Proc. Am. Acad. 15: 45. 1880. Roots a 

 fascicle of fleshy fibers: stems 10-15 cm. high: leaves petioled, soft-pilose 

 when young, soon glabrtitc, from oblong to obovate-spatulate, 3-10 toothed: 

 sepals very dark-villous: petals crenulate, about 1 cm. long: carpels glabrous, 

 Bubgloboee, beaked by a short straight style. Alpine; in southwestern 

 Colorado. 



7. Ranunculus abortivus L. Sp. PI. 551. 1753. Glabrous, 1-5 dm. high: 

 primary root-lea ves round heart-shaped or kidney-form, barely crenatr, the 

 succeeding ones often :;-lobcd or 3-parted; those of the stem and branches 

 :', .Vparted or divided, their divisions oblong or narrowly wedge-form, mostly 

 toothed: petals shorter than the reflexed sepals: achenes with a minute 



