36 



petiolatis ; natantibus oblongis ellipticisve ionge petiolatis coriaceis 

 saepe deficientibus, pedunculis apicein versus incrassatis, fructibus 

 recentibus compressis margine obtusis, caule ramosissimo. 



a. graminifofius <Tries Novit. Fl. suec. ed. 2, p. 36. — Koch Syn. ed. 2, p. 777) 



foliis submersis oblongo-linearibus utrinque altenuatis flaccidis, caule elongato. 



P. gramincus. Gorter Fl. ingr. p. 26. — Kalm Fl. fennic. No. 99. — Lepech. 



It. III, p. 134. — Falk Beitr. II, p. 120. — Gilib. Exerc. phytol. II, p. 424. 



c. icone. — Stephan Ft. mosq. No. 111. — Georgi Beschreib. d. liuss. R. 



III, 4. p. 747. — Jundz. Fl. lithuan. p. 48. — Mart. Fl. mosq. p. 32. — 



Fei.lm. Ind. Lappon. No. 73. — Fieisch. et Lindem. Fl. d. Ostseeprov. 



p. 65. — Wirzen Casan No. 655. — Nylander Paroec. Pojo. No. 350. 



/3. heterophgllus (Fries Nocit. Fl. suec. ed. 2, p. 37. — Kocn l. c.) foliis sub- 



mersis brevioribus recurvatis; natantibus petiolatis coriaceis. 



P. heterophyllus. Schp.eb. Spicil. Fl. lips. p. 21. — Georgi Beschreih. d. 



Russ. R. III, 4. p. 746. — Fellm. lnd. Kola. No. 83. — Eichw. Skitsze 



p. 126. — Hofft Cat. Kursk. p. 12. — Weinm. Fl. petropol. p. 20. — 



Fleisch. et Lindem. Fl. d. Ostseeprov. p. 65 (sub nom. hybridi Thuillier). 



P. Proteus heterophyllus. Chamiss. et Schlechtend. in Linnaea II, p. 202. — 



Chamiss. ib. VI, p. 590. — Erman Verx. No. 23. 



Hab. in Rossia [ubique (Falk)] arctica [territor. Kola (Fellman), Lapponia! 



(Fellm. , Schrenk pl. exs.)] , sep t e n t ri o na ii [Ostrobothnia (Nylander in 



litl.) , Fennia (Kalm, Nylandep.)] , media [Pi-tropoli (Gorter , Chamiss., 



Weinm.), Esthonia, Livonia ! et Curonia (Fleisch. et Lindem.), Lithuania, 



(Gilib., Jundz., Eichw., Wolfgang pl. exs.), Kursk (Hofft), Mosqua (Stephan. 



Mart.), Kasan (Wirzen), Wiatka (Lepech.). 4. 



10. P. nitens (Weber Fl. holsat. Suppl. No. 11, sec. Nolte 

 Novit. Fl. holsal. p. 18) foliis submersis membranaceis pellucidis lan- 

 ceolatis v. lineari-lanceolatis acutis muticis basi rotundatis semiamplexi- 

 caulibus margine scabriusculis; natantibus oblongis lanceolatisve iu 

 petiolum attenuatis coriaceis saepe deficientibus , pedunculis apicem 

 versus plerumque crassioribus, fructibus exsiccatis compressis margine 

 carinatis, caule ramosissimo. 



F. nitens. Fries Novit. Fl. suec. ed. 2, p. 34. — Koch Syn. ed. 2, p. 778. — 



Nylander Spicil. pl. fennic. I, No. 23. 

 a. salicifolius: foliis submersis lineari-lanceolatis strictis, caule elongato. 



P. gramineum. Wahi.enb. Fl. upsal. p. 57. 

 /?. heterophyllus : foliis submersis brevioribus lanceolatis quandoque ovato-lanceo- 

 latis recurvis, caule breviore ramosissimo. 

 P. curvifolius. Hartm. Scandin. ed. 2, p. 45. — Eichw. Skime p. 126. 



Hab. a. in Rossia s eptc nt ri o n ali [Fennia (Nylander)]; — (3. in Rossia 

 sep t e n t r io n a 1 i [Fennia (Nylander;] et media [in fl. Diina (Eichw.)]. 2[. 



Sect. II. Homophylli. Koch Syn. ed. 2, p. 778. 



Tota planta submersa : spicis sub antliesi tantum emersis. Folia 

 alterna ; floralia opposita; omnia membranacea, forma varia : oblonga, 

 elliptica v. orbiculata. 



11. P. lucens (L. Spec. 1S3) foliis omnibus submersis membra- 

 naceis pellucidis ellipticis oblongisve in petiolum brevem attenuatis 

 mucronatis margine serrulato-scabris , pedunculis sujierne incrassatis, 

 fructibus recentibus compressis margine obtusis leviter carinatis, 

 caule ramoso. 



P. lucens. Koch l. c. — Kunth Enum. III, p. 132. — Gorter Fl. ingr. p. 25. 

 — Kalm Fl. fennic. No. 96. - S. G. Gmel. It. IV, p. 15. — Lepech. lt. III, 



