210 Karl M. Wiegand and Arthur J. Eames 



8. Ranunculus (Tourn.) L. 10 



a. Flowers white ; petals with no scale over the nectary at base ; achenes wrinkled ; 

 floating (sometimes stranded) aquatics with dissected leaves. 

 b. Leaves short, very closely sessile, strongly clasping, subrigid; peduncles stout; 



styles 1 mm. long in fruit. 1. R. longirostris 



b. Leaves longer, less closely sessile, not clasping, rigid or flaccid; peduncles at 

 flowering time averaging longer and more slender ; petals slightly narrower ; 

 style obsolete or nearly so. 2. R. aqitatilis, 



var. capillaceus 

 a. Flowers yellow; petals with a scale at base; achenes wrinkled; floating (sometimes 

 stranded) aquatics with the immersed leaves dissected (see also 3d a). 



3. R. delphinifolius 

 a. Flowers yellow ; petals with a scale at base ; achenes not wrinkled ; terrestrial plants. 

 b. Achenes striate, thin-walled ; plants very low, scapose, spreading by runners ; 



leaves suborbicular, crenate ; flowers very small. 4. R. Cymbalaria 



b. Achenes smooth, not striate, thicker-walled. 

 c. Flowers small, 1 cm. in diam. or less. 

 d. Plant glabrous. 



e. Leaves linear, entire; plant creeping, rooting at the nodes. 



5. R. reptans, 



var. ovalis 

 e. Leaves, at least the basal ones, suborbicular, crenate; plant erect. 

 /. Basal leaves lobed or parted; stems stout, hollow; achenes 0.8-0.9 mm. 



in diam. ; heads oblong, very-many-fruited. 6. R. sceleratus 



f. Basal leaves mostly not lobed; stems slender; achenes 1.2-1.7 mm. in 

 diam. ; heads subglobose, few-fruited. 7. R. abortivus 



d. Plant hirsute. 



e. Styles hooked in fruit; heads subglobose; leaf divisions sessile. 



8. R. recurvatus 

 e. Styles straight or nearly so; heads oblong; terminal division of the leaf 

 stalked. 9. R. pennsylvanicus 



c. Flowers large, 1.5-2.5 cm. in diam. 

 d. Styles in fruit 1 mm. long or longer, straight or more or less recurved. 

 e. Petals narrowly obovate or oblong ; achenes 2-2.6 mm. in diam. ; plants 

 not stoloniferous, all elongated branches terminated by flowers; more or 

 less silky villous plants of dry soil. 

 /. Roots much thickened, fleshy; cauline and later radical leaves pinnately 

 cleft or divided, the lobes or divisions narrow, linear-lanceolate. 



10. R. fascicular is 



f. Roots scarcely thickened ; leaves palmately or pedately 3-clef t or divided, 

 the lobes or divisions broad, oval or obovate to oblanceolate. 



11. R. hispidus, 



var. falsus 



e. Petals broadly obovate; plants stoloniferous, with elongated, prostrate, 



leafy, flowerless branches ; glabrous or hirsute plants, chiefly of moist 



or wet soil. 



/. Achenes 3-3.4 mm. in diam. ; styles nearly straight, more than half the 



length of the achene; plant glabrous or slightly villous. 



12. R. septentrionalis 

 f. Achenes 2-2.5 mm. in diam. ; styles more or less curved, one-half or less 



than one-half the length of the achene. 

 g. Flowers single ; leaf divisions cuneate at base, sharply lobed. 

 h. Pubescence appressed. 13. R. repens 



18 R Ficaria L. has been found near yards where cultivated, but is doubtfully established. It 

 occurs in Cascadilla woods. 



