18 THE JOURNAL OF BOTANY 
has been proposed for one or vues - them, but Tausch’s descrip- 
tion (1834) is too vague: “ Bat um ; caule abbreviato natante, 
foliis omnibus immersis petiolatis capillaceo-multifidis, floribus 
is sub-12-andris oligocarpis, carpellis hispidulis obtusis.” 
Of the two it rather applies to R. divaricatus. 
Segregatory pms of the plants here comprised under 
fi. aquatilis L. v 
I. R. Divaricatus he (1789). 
1. CoMMUNIS. 
lusus MACRANTHUS. 
Var. 2. ERADICATUS = FR. aquatilis var. eradicatus Leestad. 
1842). 
lusus ee ig 
ae FURCATU 
Var. 3. Rion = R. Rionéi Lagger (1 
Var. 4. ainsi 1= f. Ase mith pear Fe ore 
Var. 5. SPHEROSPERMUS = Ft. spherospermus Boiss. et 
Blanche (1856). 
Var. 6. caBomBomDEs = FR. hydrocharis var. cabomboides 
W. P. Hiern (187 
Var. 7, TERRESTER = R. Drouetii f. terrestris G. C. Druce 
(1897). 
II. R. rrichorHytuvus Godron (1847). 
Var. 1, CoMMUNIS. 
forma TYPICA. 
forma FILICAULIS Rouy et Fouc. (1893). 
forma poLicnopopa = RF. dolichopodus A. Kerner 
(1893). 
forma NUTANS. 
forma CARNOSA = a confervoides var. car- 
m J. M. Norman (1893). 
forma NANA ee ats (1904). 
Var. 2. oe tom a oh 
forma CREBRIOR. 
forma Gacenk: J 
I.—Ranvuncvunvus prvarrcatus Schrank. i 
The history of this noes from 1539 to 1739 is a in’ 
the following list of names of the plant, verified by comparison « 3 
the text and figures in the authors cited :— 
~~ Kreut, Bock (afterwards Tragus) Kreutterbuch, ii. ch. 43, 
XXXli oo 1539), reprinted as Kreuter B uch (Strass- 
ae. agus (formerly Bock), Latin edition by D. Kyber, _ 
ibe ii. a ign ora p. 687 i 1552). : 
Hous ig us chamemeli foliis, Gesner Tab. Collect. 104 (st g 
1553). 4 
Steak: aquaticum quoddam, a lc. p. 90b. ¥ 
bat 
