KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 55. N:0 5- 



179 



belg. 1827, 163. — P. Hornemanni Meyeb, ex Kocir, Synopsis, 1837, 674. - P. 

 microcarpus Boiss. & Reitt., Diagn. Pl. nov. Hisp, 1842, 24? — P. siculus Tineo 

 ap. Gussone, Fl. Sic. Syn., II, 1845, 790. — P. subflavus Loret & Barrandon, 

 Flore de Montpellier, 1876, 671. 



The floating leaves of this species are generally thinner than in other species 

 dependent on a reduction of the palisade-tissue into one or 2 cell-strata of cubic cells 

 without the air-rooms appearing there otherwise. Rarely we meet with leaves with 

 air-cells in that tissue, which then is very like ordinary palisade tissue. Apex of 

 the floating leaves usually obtuse without distinct cuspidation or 

 pointing (see fig. 93, B). Exceptionally there are individuals with 

 the upper leaves cuspidate. I name this form: 



f. cuspidatus n. f. — Folia superiora cuspidata (vide fig. 93, A). 



Sometimes the floating leaves are small, 20—30 X 10 — 15 

 mm, and the submersed leaves narrow: 



f. subflavus n. f. — P. subflavus Lor. & Barr., 1. c. — Spe- 

 cimens from France, Mauguio (Hérault) 73, Loret and others 

 (hb. Stockholm, et Lund.) and from Germany, Daunstadt (Palati- 

 nat) 55, Schultz (hb. Stockholm, et Uppsal.). 



This plant is still held for a subspecies of P. alpinas Balb. 

 by Prof. P. Graebner in his Synopsis der Mitt. Fl. 1912 p. 476 

 (2d ed. III Lief.). Prof. G. Fischer writes (in Fedde, Repert. 

 1914) of the same plant: — »certe et habitu et fructu distat a P. 

 alpinus Balb. et accedit ad P. coloraium. Utrum autem subspe- 

 cies vel proles P. colorati, an planta hybrida inter P. coloratum 

 et P. alpinum (vix P. polygonifolium) habendus sit, adhuc am- 

 bigitur». 



The Héraultian plant is without any doubt a true form of 

 P. coloratus and not at all of a hybrid origin. — 



A form with rounded, o väte, superior leaves, ca. 30 X 24 mm, 

 is v. rolundifolius Mert. & Koch. — Now and then forms appear vahl. a, invoiuorai ieaf 



i i ►,/-> o/-. i i nA Å - °f * ne form cuspidatus Hag- 



with very large leaves, /0 — 80 mm long or more, by 30 — 45 mm st*, f #, Top of an in- 



i j volueral leaf of the eom- 



Droaa: mon i0l . m> i 



f. grandifolius n. f. — Folia amplissima, 70 — 80 X 30 — 45 mm. 



Var. pachystachyus Rchb. has thicker spikes than the other forms (not seen by 

 me). — Var. jamaicensis Griseb., to judge from the description, may not at all be- 

 long to this species, the plant occurring aside from the distribution-area, and the 

 fruit being half as large as in P. lucens and sharply keeled, the stipules keeled etc, 

 see Grisebach, Fl. Br. West Ind. Isl. 1864, 506! 



The terrestrial form, f. terrestris Tiselius, is very often seen. 



Distribution. Siveden, Scania, Eskilstorp, 91, Larsson and others (hb. Stock- 

 holm., Uppsal., Lund.), Bulltofta, 94, Johansson and others (hb. Stockholm., Upp- 

 sal., Lund.), Arrie, 67, Tullberg and others (hb. Stockholm., Uppsal., Lund. et 

 Gothob.). Bleking, Marielund, Aspegren, hb. Hartman (hb. Uppsal.), labelled: 



Fig. 93. P. coloratus 



