68 FOUMS AND DISTRIBUTION OF BATRACHIUM. 



PI. Ex3. 1859. R. agiint'iUs, a. diver sifolius, Hagen, Eaniinc. 

 Pmss. (1783) in Liulw. Del. Opiisc. p. 587 (1790). R. aquatUis, 

 Tluiill. PI. Far. ed. ii. p. 278 (1799), Naccari PI. Venet. vol. iii. 

 p. 101. n. 510 (1827). R. h^drocharls, A. heteropliyllus, Spenn. 

 PL Prib. p. 1007 (1829). Batrach'mm aquatUe, p. heteropJiyllum, 

 Spach Hist. Nat. Veg. vol. vii. p. 200 (1839). Batrachium, 

 sect. Hetkrophylle/K, Dumort. Mouogr. (1863). B. lideolum, 

 Eevel, Recli. Bot. Sud-oiiest Prance (1865) ; Bull. Soc. Bot. 

 Prance, vol. xii. Eev. Bibl. p. 258 (18 G 5), is a form having the 

 leaves (all) reniforra subrotundo-orbicular, 3-5-fid, with crenate 

 lobes, flowers small, carpels nnmerous, style sublateral, receptacle 

 setose. When in nearly dry places the stem is procumbent and the 

 floating leaves are subreniform, tripartite, with more or less di- 

 vided lobes, and the submersed leaves multihd with linear segments, 

 the state is R. aquatills, C. anomalus, Liljebl. Sw. PL p. 229, ex 

 Schlechtendal ; R. aquatiUs, a. heterophi/Uus, ccenosns, Moris PI. 

 Sard. vol. i. p. 26 (1837); R. aquatilis, y. terrestris, Godr. 

 When the floating leaves tend to become capillary, as in Biria, 

 Hist. Eenonc. t. 1. f. 27, the state is called radlatus [see Boreau, 

 PL Cent. Pr. ed. 3. voL ii. p. 11 (1857)] or fissifoUns [see 

 Schlecht. Berol. PL vol. i. p. 303 (1823)]. When submersed 

 leaves are entirely absent (a very rare occurrence in the oq/uiiilis 

 group), the state is called isophyllits [see Pries, Sum. Veg. Scand. 

 vol. i. p. 26 (1846)] ; and when this takes place in shallow places 

 which subsequently become dry, so that the lower leaves wither 

 and the upper only remain, the state is R. aquatilis a. anomalus, 

 Retz ex Schlechtendal. Batrachium heterophylhim, var. crassi- 

 caulis. Pries, Sum. Yeg. Scand. vol. i. p. 140 (1846) is a succulent 

 state with swelled stem, large flowers, many stamens, and about a 

 hundred glabrate carpels arranged in a large head ; perhaps a state 

 oi Baudotii. Porms 8-19. 



8. TRIPARTITUS. 



ii;. tripartitus, De Cand. le. PL Gall. Par. p. 15. t. 49 (1808) excl. 

 Syn. Thor., non Auct. Brit, nee Nolle (1828), nee PL Dan. t. 1993. 

 R. tripartitus, a. micranthus, De Cand. llegn. Veg. Syst. Nat. vol. i. 

 p. 234 (1818). Batrachium. tripartitum, S. P. Gray, Nat. Arr. Br. pi. 2. 

 721 (1821). R. hydrocharis, A. heterophyllus, y. tripartitus, Spcnn. PL 

 Prib. (1829).— Pig.— Sturm, Deutschl. PL Hf. 67 ; Peichb. PL Germ. 

 3. 2 ; Godr. Essai, f. 3 ; Cosson and Germ. Atl. t. 1. f. 7, 8. 



Occurs in Prance, Germany, Portugal, Spain (Willkomm ! a weak 

 state with long and slender petioles and without submersed leaves, and 

 with the floating leaves nearly tripartite, and also with the receptacle 

 setose and sometimes conical ; approaches interuiedius, Lobhii, nndteiiellus, 

 as well as tripartitus). Another plant in flower from Portugal (AVel- 

 witsch 1 PL Lusit. Exs. 409) without floating leaves and resembling 

 confervoides, is R. tripartitus, (3. suhmersus, Godr. in Gren. and Godr. PL 

 Pr. vol. i. p. 20 (1848). Pries states in Sum. Veg. Scand. vol. i. p. 140 

 (1846), that the ])resence of floating leaves is necessary for the production 

 of flowers in R. tripartitus, De Cand., in consequence of the peduncles 

 springing only from the axils of the floating leaves. 



R. aquatilis, A. heteroph/llus, a. lejospei'mns, Wallr. Sched. 

 Crit. 282 (1822). R. Fetiveri, Koch, Syn. PL Germ, et 



