ME. F. C. S. EOPEH ON EANUNCULUS XINGUA. 383 



green throughout the winter." Again Boreau, in his PI. du cent, 

 de la Fr. edit. 3 (1857), says of R. Lingua, " produisant sous l'eau 

 des feuilles longuement petioles, larges, cordiformes ovales." 

 In Symes's Eng. Bot. ed. 3, 1863, we find:— "The earliest leaves, 

 and those of the barren shoots on loug stalks, ovate or oblong- 

 ovate, those on the flowering-stem sessile, linear-lanceolate, very 

 acute, faintly and remotely denticulate or nearly entire." Lloyd, 

 in his Fl. de 1'ouest de la Fr„ 3rd edit. (1876), says :— " Feuilles 

 demi-embrassantes lanceolees-lineaires, a dents courtes, obtuses, 

 eloignees, les radicales submergees en coeur-ovales." And finally, 

 Prof. Babington, in the 8th edition of the ' Manual,' 1881, after 

 describing the stem-leaves as in previous editions, adds " early 

 submerged leaves oblong, blunt, cordate at the base." 



There is one point of interest about the submerged leaves of 

 It. Lingua worthy of notice, and that is, that though the large, 

 broad, early leaves are always submerged, never, as far as I have 

 seen, even floating on the water, yet they have a considerable 

 number of small oval stomata, as shown in PL XIII. fig. 2, about 

 ■£$-5 of an inch in length ; similar in shape, but far less numerous 

 and smaller in size than those on the aerial leaves, on which they 

 are very abundant, and about F ^ of an inch in length, as shown 

 in PL XIII. fig. 3. In most works on Structural Botany, stomata 

 are said to be absent on submerged leaves. Sachs, however, 

 states that they are occasionally found. May not their presence 

 in M. Lingua tend to show that the submerged are modified 

 aerial leaves, rather than that the large spreading submerged 

 leaves have been contracted and modified by exposure to air ? 



Plate XIII. represents a plant of Eanunculus Lingua, collected 

 in February 1878, whilst the whole plant was entirely submerged, 

 drawn to scale of rather less than half the natural size. PI. XIV. 

 shows a plant collected in May of the same year, showing the 

 flowering-stem, with one of the submerged leaves still remaining. 

 PL XIII. fig. 2 are the small stomata from the submerged leaves; 

 and PL XIII. fig. 3 are the larger stomata from the aerial leaves. 



DESCRIPTION OF THE PLATES. 

 Plate XIII. 

 Fig. 1. Submerged leaves of Eanunculus Lingua, L., slightly less than half nat. 

 size, from a marsh-ditch in Pevensev Levels, near the Waterworks, 

 Eastbourne. Collected Feb. 21, 1878. 



2. Stomata from submerged leaves, ,,J ff in. long, X200. 



3. Stomata from aerial leaves, , Jar in. long, X 200. 



