118 THE JOURNAL OF BOTANY 



Exsiccata : — Billot, 3801, as B. confusus ; Fries, xv. 28, as 

 B. confusum ; Wirtgen, ix. 437, as B. 2)etiveri. 



In the above remarks it has, of course, been necessary to 

 refer to plants which are related (either botanically or in nomen- 

 clature) to B. ohtusiflorus ; and below will be found the species 

 (as I understand them) of the section Batrachium of western 

 Europe, with the full citations of the various plants referred to in 

 the present communication. The citations are placed after the 

 names of the species to which I consider they belong. A dash is 

 placed before those names which, in my opinion, ought to be 

 distinguished as subspecies or varieties. In recognising nine 

 west-European species of the section Batrachium, I am following 

 several leading modern authorities. Syme (1863) united B. aqua- 

 tilis and B. tricJiophyllus; but otherwise his species were the 

 same as those given below. Hooker (1884) and Eouy & Foucaud 

 (1893) adopted precisely the species which are here given. 

 Bentham (Handbook Brit. Fl. 59, 1858) reduced them all to one 

 which he named " B. aquaticus Linn." [sic] ; but I know of no 

 modern systematic botanist in Europe who would now accept 

 Bentham's view of species ; whilst Babington (Man. ed. 9, by 

 H. & J. Groves, 1904) divided the section into sixteen species. 



1. E. HEDERACEUS L. Sp. PI. 556 (1753) ! 



2. E. HOMioPHYLLus - Tonore Fl. Nap. iv. 338 (1830); 

 B. ccenosus Gussone Suppl. Fl. Sic. Prodr. fasc. ii. 187 (1834) ! ; 

 Godron in Grenier & Godron Fl. France, i. 19 (1848)!; B. lenor- 

 mancli Schultz in Bot. Zeit. xx. 726 (1837) ! — ? Batrachium 

 lutarium Eevel in Act. Soc. Linn. Bordeaux, xxv. 413, t. 4 

 (1865); B. Uitarius Bouvet in Bull. Soc. Angers for 1871, 96 

 (1872). 



3. E. TRiPARTiTus DC. Icon. PI. Gall. Ear. 15, t. 49 (1808) ; 

 N. E. Brown op. cit. 13 (1891) excl. syn. Knaf ; B. iripartitus var. 

 micranthus DC. Syst. Nat. i. 234 (1818) ; Batrachium trijmrtitum 

 Gray Nat. Arr. Brit. PL i. 721 (1821) ; form tripartitus Hiern op. 

 cit. 68 (1871) ; — form intermedius Hiern op. cit. 67 (1871) excl. 

 syn. Knaf ; B. lutarius ['? Bouvet, loc. cit.] H. & J. Groves in 

 Journ. Bot. xlv. 452 (1907). 



4. E. HOLOLEUCUS Lloyd Fl. Loir.-Inf. 3 (1844) ; B. petiveri 

 Cosson & Germain Fl. Env. Paris, 10, Atlas, t. i. fig. 5-6 (1845) 

 non Koch. 



5. E. OBTUsiFLORUS Moss. SsB abovB. 



6. E. AQUATiLis L. Sp. PI. 556 (1753) excl. vars. ; Godron 

 Essai in Mem. Soc. Eoy. Nancy, 24 (1838) ; Koch, Syn. ed. 2, 

 12 (1843) ; B. heterojjhyllus Wiggers Fl. Hols. 42 (1780) ; Hooker 

 fil. op. cit. 5 (1884) ; B. diversifolius Gilibert Fl. Lituan. iii. 262 

 (1782) ; Eouy & Foucaud Fl. France, i. 63 (1893) ; non Schrank; 

 Batrachi^Lvi heterophyllum S. F. Gray op. cit. 721 (1821) ; — 

 B. triphyllos Wallroth in Linnaea, xiv. 584 (1840) ; form tri- 



The justification of this citation may form the subject of a future note. 



