5. R. ámbigens, Watson. (WATER PLANTAIN SPEARWORT.) Stems ascending (1--2° high), often rooting from the lower joints; leaves lanceolate or the lowest oblong, mostly denticulate (3--5´ long), contracted into a margined half-clasping petiole; petals 5--7, bright yellow, oblong (2--3´´ long); _carpels flattened, large_ (1´´ long), _pointed with a long narrow-subulate beak_. (R. alismæfolius, _Man._, not _Gey._)--N. Eng. to Ont., Minn. and southward; common, especially at the north. June--Aug. 6. R. Flámmula, L. (SMALLER SPEARWORT.) Stem reclining or ascending, rooting below, leaves lanceolate or linear, or the lowest ovate-oblong to lanceolate, entire or nearly so, mostly petioled (1--2´ long), petals 5--7, much longer than the calyx, bright yellow, _carpels small, flattish but turgid, mucronate with a short abrupt point_.--Only a small form (var. INTERMÈDIUS) met with in this country (shore of L. Ontario, and northward), a span high, with flowers 3--5´´ in diameter, passing into Var. réptans, E. Meyer. (CREEPING S.) Small, slender, the _filiform creeping stems rooting at all the joints_; leaves linear, spatulate, or oblong (¼--1´ long); flowers small.--Gravelly or sandy banks; Newf. to Penn., north and westward. June--Sept. (Eu.) 7. R. oblongifòlius, Ell. Usually annual; stem erect or ascending, often pubescent below, slender (1--2° high), _diffusely branched above and many-flowered; leaves serrate or denticulate_, lower long-petioled, ovate or oblong (½--1½´ long), uppermost linear; flowers 3--5´´ broad; _petals_ 5, bright yellow, 1--3´´ long; _carpels_ minute, almost _globular_, the small style deciduous.--Wet prairies, Ill., Mo., and in S. States. June. 8. R. pusíllus, Poir. Stem ascending, weak, loosely branching (6--18´ long); _leaves entire_ or obscurely denticulate, the lowest round-ovate or heart-shaped (½´ long), long-petioled, the upper oblong or lanceolate (1--1½´ long); _flowers very small; petals 1--5, yellowish_; stamens 3--10; carpels very turgid, smooth or slightly papillose, tipped with a minute sessile stigma.--Wet places, S. New York, and southward along the coast. June--Aug. [+][+][+] _Terrestrial, but often in wet places; leaves mostly cleft or divided._ [++] _Root-leaves not divided to the very base; achenes marginless._ 9. R. affìnis, R. Br. Somewhat hairy or glabrous; low or slender, 1° high or less; leaves pedately cleft, the cauline with linear or narrow oblanceolate divisions; petals light yellow, 3--4´´ long or smaller; _heads oblong; achenes turgid_, with small and mostly recurved style, pubescent or glabrous.--And var. VALIDUS, Gray, stouter and with more fleshy leaves, the lower mostly undivided and roundish, cordate, truncate or cuneate at base, coarsely crenate or more or less cleft.--Minn., Iowa, north and westward.