394 RANUNCULACEAE (CROWFOOT FAMILY) 



1. RANUNCULUS [Tourn.] L. Crowfoot. Buttercup. 



Annuals or perennials ; stem-leaves alternate. Flowers solitary or somewhat 

 corymbed, yellow, rarely white. (Sepals and petals rarely only 3, the latter often 

 more than 5. Stamens occasionally few.) — (A Latin name for a little frog; 

 applied by Pliny to these plants, the aquatic species growing where frogs abound.) 



§ 1. FICARIA Boiss. Boots tuberous- thickened ; sepals 3; petals about 8, 

 yellow, with a free scale over the honey gland. 



1. R. FicXria L. (Lesser Celandine.) Glabrous and somewhat succu- 

 lent ; leaves basal on long stoutish petioles, ovate, rounded, deeply cordate, sub- 

 crenate; flowers scapose, 2 cm. in diameter. {Ficaria Karst.) — Wet places, 

 occasional ; Mass. to D. C. Apr., May. (Introd. from Eurasia.) 



§ 2. BATRACHIUM DC. Petals with a spot or naked pit at base, white, or 

 only the claw yellow; achenes marginless, transversely ivrinkled ; aquatic 

 or subaquatic perentiials, with the immersed foliage repeatedly dissected 

 (mostly by threes) into capillary divisions ; peduncles 1-flowered, opposite 

 the leaves. 



* Beceptacle hairy. 



2. R. circinatus Sibth. (Stiff Water C.) Leaves all under water and 

 sessile, with broad conspicuous stipules, the divisions and subdivisions short, 

 spreading in one roundish plane, rigid, not collapsing when withdrawn from the 

 water. (R. divaricatus auth., not Schrank ace. to Hiern.) — Ponds and slow 

 streams, Vt. to Pa., la., northw. and westw., rather rare. (Eu.) 



3. R. aqudtilis L., var. capillaceus DC (Common White Water C.) 

 Leaves all under water and mostly petioled, their capillary divisions and sub- 

 divisions rather long and soft, usually collapsing more or less when withdrawn 

 from the water; petiole rather narrowly dilated. {B. aquatilis, var. trichophyl- 

 lus Gray ; Batrachium trichophyllum Bosch ; B. flaccidum Rupr. ; B. Drouetii 

 Nym. ; and B. confervoides auth., not Fries.) — Common, especially in slow- 

 flowing waters, the eastern form with more soft and flaccid leaves. June- 

 Aug. (Eu.) Var. caespitosus DC. A dwarf terrestrial variety or possibly 

 mere state, rooting at the nodes, the small leaves somewhat fleshy, with broader 

 rigid divisions. — S. 111. {Schneck), and westw. (Eu.) 



* * Beceptacle glabrous; no submersed leaves. 



4. R. hederAceus L. Rooting freely in shallow water ; leaves all reniform, 

 angulate-lobed. (Batrachium S. F. Gray.) — Fresh-water marshes, Nfd. ; 

 s. Md. ; s. 6. Va. (Nat. from Eu.) 



§ 3. H AL6deS Gray. Petals yellow, with nectariferous pit and scale ; carpels 

 thin-walled, striate, in a subcylindric head; scapose, spreading by runners. 



5. R. Cymbalaria Pursh. (Sea-side C.) Glabrous; scapes 4-22 cm. high, 

 1-7 -flowered ; leaves clustered at the root and on the joints of the long rooting 

 runners, roundish-heart-shaped or kidney-shaped, crenate, rather fleshy, long- 

 petioled ; petals 5-8. ( Oxygraphis Prantl. ) — Lab. to N. J. , also along the Great 

 Lakes and in alkaline soil of the interior. June-Aug. (Greenl., Eurasia.) 



Var. alpinus Hook. Dwarf ; leaves 3-toothed, only 3-6 mm. broad. — Cape 

 Breton I., N. S., e. Que., and northw. 



§4. EURANUNCULUS Gray. Petals with a little scale at the base, yellow; 



achenes nerveless. 



* Achenes smooth, or nearly so ; mostly perennial. 

 t- Aquatic; immersed leaves filif or mly dissected; as in § Batrachium. 



6. R. delphinifblius Torr. (Yellow Water C.) Stems floating or im. 

 mersed, with the leaves all repeatedly 3-forked into long filiform divisions, or 

 sometimes creeping in the mud (perennial by rooting from the nodes, if at all) ; 

 petals 5-8, deep bright yellow, 8-12 mm. long, much larger than the sepals; 



