Mr. C. C. Babington 07i the Batrachian Ranunculi. 393 



approach to a floating leaf, such as is occasionally although 

 rarely found upon our plant, may be detected upon M. Lenor- 

 mand's specimens. Of this, however, I am not quite certain. 



I am much indebted to my friend the Rev. W. W. Newbould 

 for directing my attention to the floating leaves of our plant. 



The R. Godronii (Gren.), specimens of which I have received 

 from Dr. F. Schultz, appears similar to our plant when it is 

 furnished with the floating leaves, but T am unable to see in 

 what other respects it diffbrs from the typical R. Drouetii. I 

 cannot find any description of R, Godronii. 



R. confervoides (Fries, H. N. xiii. 45) is closely allied to this 

 species, but has long slender peduncles, i?. paucistamineus 

 (Tausch) may be a stronger form of R. confervoides. 



R. Drouetii can only be confounded with R. trichophyllus or 

 R. heterophyllus. From the former it is distinguished by its 

 bright green colour, collapsing leaves, inflated and very blunt 

 carpels, and much more lax habit ; from the latter by its very 

 peculiar floating leaves, fewer-nerved and evanescent petals, 

 inflated and minutely apiculate carpels, and nearly globose 

 receptacle. 



Flowering in May and June. 



I have received R. Drouetii from several places in Cambridge- 

 shire, Burnham in Norfolk, Byford in Herefordshire, and Hook 

 in Surrey. 



3. R. heterophyllus (Fries) ; submersed leaves loosely trifurcate, 

 segments long collapsing, floating leaves subpeltate tripartite 

 with sessile or stalked wedge-shaped 3-5-lobed leaflets, pe- 

 duncles not narrowing scarcely exceeding the leaves, flowers 

 large, petals broadly obovate-cuneate 7-9'nerved not con- 

 tiguous persistent, stigma oblong, receptacle conical, carpels 

 4-ovate laterally pointed. 



R. heterophyllus. Fries, Summa, 140, & Herb, Norm. ii. 32 (spe- 

 cimen). 



R. aquatilis a. pseudo-peltatus, Godr. in Mem. de Nancy, 1839, 

 p. 25. f. 5 c & g. 



R. aquatilis var. pantothrix. Fries, Herb. Norm. ix. 27 (specimen). 



R. aquatilis, Eng. Bot. t. 101. 



Batrachium heterophyllum, Fan den Bosch, Prod. FI. Batav. 8. 



Stem floating, rooting from the lower joinings, prominently 

 but irregularly angular, hollow. (A plant apparently referable 

 to this species which grew in shallow water has a solid stem. 

 Much stress has been laid upon such a diff'erence, but it seems 

 of little consequence.) Submersed leaves two or three times 

 trifurcate, afterwards bifurcate ; segments filiform, rather rigid. 

 At the first fork the branches are divaricate and the middle one 



