RANUNCULUS 
141 
(/ 3 ) forma aquaticus nobis. 
leones : — Camb. Brit. FI. iii. Plate 14.5. (a) Fertile branches, (b) Petals (one enlarged). ( c ) Achenes 
(enlarged). West Riding of Yorkshire (W. H. C.). 
This is the state which occurs in deep and sometimes even in quick-running water : it is larger in all its parts than 
the mud-form. The laminae are usually 5-lobed, and the petals are longer than the sepals. It seems to be the form originally 
described by Tenore and Gussone, whilst the mud-form is the state more generally known. 
Locally common in swamps, ponds, ditches, and streamlets, usually in shallow water ; preferring 
non-calcareous soils and waters with a low mineral-content, sometimes growing even in acidic water ; 
from Cornwall and Kent northwards to Dumbartonshire, chiefly in the western and northern parts of 
England, in Wales, and in southwestern Scotland, ascending to 490 m. on the Pennines in Derbyshire ; 
southern Ireland. 
Belgium, France, Spain, Portugal, Italy (inch Sicily); Algeria. 
R. aquatilis X homoiophyllus comb. nov. ; R. lenormandi x peltatus H. and J. Groves in Journ. Bot. 
xxxix, 121 (1901); x R. hiltonp H. and J. Groves loc. cit. 
leones : — H. and J. Groves in Journ. Bot. xxxix, t. 420. 
leones : — Camb. Brit. FI. iii. Plate 146. (a — b) Fertile branches. ( c ) Upper leaf. ( d ) Flower-bud. 
{e) Flower. Sussex (T. H.). 
Resembling R. lenormandi in its rooting habit, the shape of the floating leaves, the number of 
stamens, and the usually glabrous carpels with rounded inner edge. Approaching R. aquatilis in the 
shape and size of the petals, and the hairy receptacle. Submerged leaves with not truly capillary, but 
the lowest ones very deeply divided into linear segments, and passing upwards by a series of gradations 
into the ordinary floating leaves. 
We have not seen this plant growing. It is a most remarkable plant, and ought to be grown under rigorous cultural 
conditions. It is without doubt close to R. homoiophyllus in some of its features ; and if that species hybridises with R. aquatilis , 
what may not be expected in the section Batrachium ? 
In a rather muddy stream in Sussex, in company with the putative parents. Not known elsewhere. 
Series ii. Aquatiles 
Aquatiles Rouy et Foucaud FI. France i, 59 (1893). 
For characters, see page 138. 
Subseries of Aquatiles 
Subseries i. Tripartiti (see below). Submerged leaves usually present, but more or less caducous 
in R. tripartitus , distinctly petioled. Floating leaves usually present, usually divided more than half- 
way. Pedicels usually longer than the leaves. Receptacle rather hairy, subglobose. Flowers o'3 — 1 o 
cm. in diameter. Petals contiguous or not. Stamens usually few (5 — 15). Achenes glabrous. 
Subseries ii. Fluitantes (p. 144). Submerged leaves very well developed, distinctly petioled, 
segments very long. Floating leaves absent. Pedicels shorter than the leaves. Receptacle ultimately 
glabrous, longer than broad. Flowers usually very large, up to 2*5 — 3-0 cm. in diameter. Petals 
contiguous or even overlapping, often more than 5. Stamens 00 , variable in length. Achenes 
glabrous. 
Subseries iii. Eu- Aquatiles (p. 146). Submerged leaves present, indistinctly petioled or sessile. 
Floating leaves often present, lobes variously cut. Pedicels as long as or rather shorter than the leaves. 
Receptacle hairy, subglobose. Flowers usually less than 2*5 cm. in diameter. Petals contiguous or 
nearly so. Stamens 5 — 00 . Achenes hairy or bristly, up to about 40. 
Subseries i. Tripartiti 
Tripartiti nobis. For characters, see above. 
British species of Tripartiti 
17. R. tripartitus (p. 142). Submerged leaves usually more or less rudimentary or even caducous 
(? ever really absent in the young state), persistent, collapsing when taken out of the water. Pedicels 
After Thomas Hilton (1833 — 1912). 
