402 Mr. C. C. Babington on the Batrachian Rauunculi. 



10. R. fiuitans (Lam.) ; leaves all submersed about twice tri- 

 furcate with very long linear twice or thrice forked nearly 

 parallel segments, peduncles narrowing, flowers large, petals 

 broadly obovate many-nerved contiguous persistent, stamens 

 falling short of the pistils, stigma cylindrical, receptacle 

 conical, carpels obovate inflated much rounded at the end 

 laterally apiculate. 



R. fluitans, Lam. FL Fr. iii. 184 ; Reichenb. Ft. exsic. 886 (speci- 

 men), et Icones Ft. Germ. iii. Ran. t. 2 ; Gren. et Godr. Fl. deFr. 

 i. 25 ; Fa7i den Bosch, Prod. Fl. Batav. 6. 



R. peucedamfolius, Desf. Atl. i. 444. 



R. fluviatilis, Sibth. Fl. Oxon. 176 ; Wallr. Sched. 284. 



R. sive Polyanthemo aquatili albo affine Millefolium Maratriphyllum 

 fluitans, Ray, Syn. 250. 



Stem floating, very long, branched above, nearly round, hol- 

 low, wholly submersed. Leaves together with their petioles 

 often a foot in length. Segments thick. Petioles of the upper 

 leaves often short. Stipules broadly lanceolate, strongly auricled, 

 ^-adnate. Sometimes at the end of the stem a few stalked 

 3-furcate leaves with short broad linear segments are found ; in 

 these leaves the middle segment is entire, the lateral ones are 

 simply forked ; they do not at all resemble the floating leaves 

 of the other species. When the seedling plant has been deserted 

 by the water, all the leaves are of this form. Bud shortly pyra- 

 midal, pentagonal. Peduncles thick, much shorter than the 

 leaves. Flower often semidouble. Sepals ovate, blunt, green, 

 bordered with purplish black and a broad diaphanous edge. 

 Petals 2-3 times longer than the calyx, slightly clawed, 9-15- 

 nerved. Nectary round, bordered slightly below. Stamens 

 many, short. Style prolonging the inner edge of the ovary. 

 Stigma straight, a little inflcxed at the top. Receptacle conical, 

 slightly pilose immediately after the flowers have fallen. Carpels 

 with a small lateral point. 



The structure of the long whip-shaped leaves is sufficient to 

 distinguish this plant. It is also remarkable for the tendency 

 of the flowers to produce a second imperfect whorl of petals. It 

 does not change its form even when growing in stagnant water. 



Not uncommon in rivers. Watson's * Cybele ' may be referred 

 to for its distribution in Britain. 



Flowering in June and July. 



The R. Bachii, Wirteu (Schultz, Archives de Flore, i. 292 ; 

 Billot, Exsic. No. 1103 !), is a form of R. fluitans. The form of 

 the petals does not aff"ord a constant character, neither does the 

 length of the peduncle. I have observed it in the River White- 

 adder in Berwickshire. It is much smaller in all its parts and 

 more elegant, but I cannot detect any other difference. Mr. 



