RANUNCULUS 
149 
often nearly parallel. Floating leaves usually not produced until about midsummer or even later, 
often few, lobes deeply and variously divided. 
This is a form growing in running water. When growing in quickly flowing streams, it simulates R. fluitans\ but its 
flowers are smaller, and its achenes are not glabrous. 
(t>) R. trichophyllus var. rigidus var. nov. ; R. trichophyllus Godron in Grenier et Godron FI. France i, 23 
(1848); Babington in Ann. Nat. Hist. ser. 2, xvi, 390 (1855); R. aquatilis var. trichophyllus Babington Man. 
ed. 3, 5 (1851); R. aquatilis subsp. trichophyllus Syme Eng. Bot. i, 23 (1863); R. hydrocharis form trichophyllus 
Hiern op. cit. 101 (1871); R. trichophyllus race trichophyllus Rouy et Foucaud FI. France i, 68 (1893). 
Segments of the submerged leaves not collapsing when taken out of the water. Floating leaves 
absent. Flowers larger than in var. droueti , appearing a fortnight later. 
This variety connects R. aquatilis and R. circinatus. 
(j 3 ) var. rigidus forma isophyllus comb. nov. 
leones: — FI. Dati. t. 2357, as R. aquatilis var. pliellandriifolius ; Babington in Eng. Bot. Suppl. t. 2968, as 
R. trichophyllus. 
Camb. Brit. FI. iii. Plate 159. (a) Fertile branch. ( b ) Leaf out of water. ( c ) Upper part of stem (enlarged). 
(d) Flower-bud. (e) Flower. {/) Receptacle (enlarged), (g) Achenes (enlarged). Huntingdonshire (E. W. H.). 
Exsiccata : — Cr£pin (in Herb. Univ. Cantab.), as B. aspergillifolium (a form with crowded and numerous leaf- 
segments) ; Fries, ix, 29, as B. circinatum ; xiii, 45 as B. confervoides (a small form); v. Heurck, ii, 51, as R. divari- 
catus ; Lloyd herb., as R. capillaceus ; Tausch {PI. Sel. FI. Boh.), as R. paucistamineus (a small form); Todaro, 
1 1 7 1 , as R. trichophyllus ; Herb. FI. Ingric., vii, 13, as B. circinatum. 
(7) var. rigidus forma terrestris nobis. 
Exsiccata: — Billot, 1203, as B. trichophyllum var. terrestre. 
This is the mud-form of the variety, and is not very rare on mud thrown out of ponds, ditches, and rivers. In summers 
of drought, it is sometimes met with in dry stream-beds. 
The var. rigidus occurs throughout the British Isles, as far north as Orkney. 
Europe. 
(c) R. trichophyllus var. droueti Loret in Loret et Barrandon FI. de Monsp. 792 (1876); R. paucistamineus 
Tausch in Flora xvii, ii, 525 (1834); F. Schultz in Arch. FI. i, 10 (1842); R. droueti [Schultz ex] Grenier in 
Grenier et Godron FI. France i, 24 (1848)!; Babington in Ann. Nat. Hist. ser. 2, xvi, 391 (1855)!; R. aquatilis 
subsp. droueti Syme Eng. Bot. i, 22 (1863); R. hydrocharis form droueti Hiern op. cit. 102 (1871) ; R. trichophyllus 
race droueti Rouy et Foucaud FI. France i, 69 (1893). 
leones : — Babington in Eng. Bot. Suppl. t. 2967, as R. droueti. 
Submerged leaves with segments collapsing when taken out of the water. Flowers smaller than 
in var. rigidus. 
This is the first member of the series Aquatiles to come into flower in the ponds and ditches of the Fen 
District, where it is locally abundant. 
(a) var. droueti forma diversifolius nobis; Batrachium godroni 1 Grenier in Schultz Arch. FI. 172 (1850)?, 
nomen ; Grenier Rev. FI. Mont. Jura 25 (no date)?, nomen; R. hydrochatis form godroni Hiern op. cit. 99 (1871). 
A number of Babington’s specimens of his R. heterophyllus , in Herb. Univ. Cantab., belong to this forma (see also 
p. 147)- 
This is the heterophyllous state of R. trichophyllus var. droueti. Some of Babington’s specimens of his R. heterophyllus 
belong to this forma diversifolius. 
(yS) var. droueti forma isophyllus nobis. 
leones : — Babington in Eng. Bot. Suppl. t. 2967 (lower figure), as R. droueti. 
Camb. Brit. FI. iii. Plate 160. (a) Fertile branch, (b) Leaf out of water. ( c ) Flower-buds (one enlarged). 
{d) Flowers (one enlarged), (e) Petals (enlarged). (/) Ovaries (enlarged), (g) Receptacle (enlarged), (h) Achenes 
(enlarged). Devonshire (W. P. H.). 
Exsiccata : — Billot, 2606, as R. trichophyllus ; Schultz {FI. Gall, et Germ.), 805 bis, as B. trichophyllum ; 
Wirtgen, ix, 435, as B. trichophyllum ; FI. Sequan. Exsicc., 1, as R. paucistamineus. 
This is the submerged form of the var. droueti, without floating leaves: it is by far the commonest form of the variety 
in the British Islands. 
1 It is usual to refer this name to the present forma ; but, as there is no available description, the matter must remain 
doubtful. 
