RANUNCULUS 
143 
(/ 3 ) forma isophyllus comb. nov. ; R. tripartitus var. isophyllus Rouy et Foucaud loc. cit. 
leones : — Camb. Brit. FI. iii. Plate 14.8. (a — b ) Flowering branches, (c) Petal (enlarged). ( d ) Flowers. 
(e) Ovaries (enlarged). (/) Head of achenes (enlarged), (g) Achenes (enlarged). Hampshire (E. S. M.). 
From what he believed to be an isophyllous form, H. C. Watson raised heterophyllous plants in 1876; and specimens 
of his heterophyllous crop are in the herbarium at Cambridge. Since Watson’s time, heterophyllous forms have been 
found growing naturally in the southern and southwestern counties. In nature, the plant is without submerged leaves at 
maturity. 
Specimens of the isophyllous state have been referred by British botanists to R. lutarius (Bouvet in Bull. Soc. Angers 
for 1871, 96 (187 2) = Batrachium lutarium Revel in Act. Soc. Linn. Bordeaux xxv, 413, t. 4 (1865)). However, R. lutarius 
is regarded as a variety of R. homoiophyllus {=R. lenormandi) by French botanists. The English plant has a hairy receptacle, and 
cannot therefore be referred to the last-named species. Mr N. E. Brown {op. cit.) referred the English plants to R. tripartitus ; 
and this view seems to us to be correct. 
R. tripartitus occurs locally in ponds and ditches ; preferring non-calcareous waters in lowland 
districts; from Cornwall and Kent northwards locally to Wales ; rather common in the New Forest; 
Ireland — counties Cork and Kerry. 
Western Europe — Belgium, France, Spain, Portugal. 
18. RANUNCULUS OBTUSIFLORUS. Plates 149, 150 
Ranunculus obtusiflorus Moss in Journ. Bot. Iii, 117 (1914); R. tripartitus var. obtusiflorus DC. Syst. 
Nat. i, 234 (1818); Batrachium obtusiflorum Gray Nat. Arr. Brit. PI. ii, 721 (1821); R. tripartitus Nolte Novit. 
FI. Holsat. 51 (1826) non DC.; R. baudoti Godron op. cit. 21, fig. 4 (1840); Babington in Ann. Nat. Hist. ser. 2, 
xvi, 395 (1855); incl. R. confusus Godron in Grenier et Godron FI. France i, 22 (1848); R. petiveri var. minor 
Koch Syn. ed. 2, 13 (1843); Batrachium baudoti van den Bosche Prodr. FI. Batav. 7 (1850) inch B. petiveri ; R. 
petiveri Cosson et Germain FI. Env. Paris 5, Atlas t. 1, fig. 5 — 6 (1845); R- baudoti [Godron ampl.] Syme Eng. 
Bot. i, 24 (1863); Rouy et Foucaud FI. France i, 65 (1893); R- marinas Hooker fil. Stud. FI. ed. 3, 5 (1884); 
R. hydrocharis form baudoti Hiern op. cit. 69 (1871) et form confusus. 
leones: — FI. Dan. t. 1993, as R. tripartitus ; Babington in Eng. Bot. Suppl. t. 29 66, as R. baudoti ; Syme 
Eng. Bot. i, t. 23, as R. baudoti var. confusus. 
Camb. Brit. FI. iii. Plate 149. {a) Fertile shoot, {b) Receptacle and pedicel (one enlarged). ( c ) Flowers. 
(d) Petals (enlarged), (e) Ovaries (enlarged). (/) Achenes (enlarged). Cornwall (C. C. V.). 
Exsiccata : — Billot, 2802, as R. baudoti ; 2802 bis, as R. baudoti var. terrestris ; 3801, as R. confusus ; 
Fries, ix, 28, as B. marinum\ Schultz {H. N.), 404, as R. baudoti ; Wirtgen, ix, 436, as R. baudoti ; ix, 437, as 
B. petiveri. 
Perennial. Shoot larger and stouter than in R. tripartitus. Sheaths adnate to the petiole for 
two-thirds of their lower length, not or scarcely auricled. Petioles of the floating leaves about 
4 — 6 times as long as the laminae, about 3 — 6 cm. long ; of the lower submerged leaves about as 
long as the laminae or a little shorter, about 1 — 3 cm. long. Submerged leaves present; segments 
usually shorter than in R. aquatilis , flat, rigid, spreading. Floating leaves present or not ; when 
present, basal sinus very broad ; rather deeply 3-lobed or 3-partite ; lobes sometimes stalked, 
cuneate, sides entire, apex more or less deeply crenate. Pedicels longer than the mature petioles, 
somewhat tapering, markedly arched in fruit. Receptacle longer than broad. Flowers about 1 - o — 
1*5 cm. in diameter; April to June. Sepals ultimately reflexed, caducous. Petals almost contiguous, 
about 1 '5 — 2 'o times as long as the sepals, obtuse-rounded at the apex. Stamens about 10 — 15. 
Stigma nearly as long as the rest of the ovary, narrow. Achenes about 60 — 100 on each recep- 
tacle, crowded, small, glabrous, beaked. 
Godron {loc. cit.), when founding his R. baudoti , states that this species has closer affinity with the group containing 
R. tripartitus than with that containing R. aquatilis ; and in this opinion we concur. 
R. obtusiflorus is sometimes confused with the heterophyllous variety of R. trichophyllus ; but the latter has shorter petioles, 
hairy achenes, and fewer achenes in each head. The floating leaves of the two species are often not dissimilar. 
(/3) forma terrestris comb, nov.; R. baudoti var. terrestris Grenier in Grenier et Godron op. cit. p. 22 (1848); 
Rouy et Foucaud FI. France i, 66 (1893). 
leones : — Babington in Eng. Bot. Suppl. t. 2966, left-hand figure. 
