The Philippine Journal of Science, C. Botany. 
Vol. IX, No. 4, August, 1914. 
THE POTAMOGETONS OF THE PHILIPPINE ISLANDS 
By Arthur Bennett 
( Croydon , England) 
Through the kindness of Mr. E. D. Merrill I have been enabled 
to examine the representatives of the genus Potamogeton be- 
longing to the herbarium of the Bureau of Science. This has 
enabled me to add one species to the flora. For the sake of 
convenience I have considered the species in the order that they 
appear in Ascherson and Graebner’s monograph of the family . 1 
I have also noted the species of surrounding countries in the 
hope that they may eventually be found in the Philippines. 
Those species which have actually been found in the Archi- 
pelago I have indicated with an asterisk. 
1. POTAMOGETON JAVAN ICUS Hassk. in Act. Soc. Ind.-Neerl 5 l (1856) 
26. 
Potamogeton heterophyllus Ham. in Wall. Cat. (1831) no. 5181. 
Potamogeton tenuicaulis F. Muell. Frag. Phyt. Austral. 1 (1858) 90 
244; 7 (1865) 217. 
Potamogeton hybridus Hook. f. & Th. (non Michx.). 
Potamogeton parvifolia Buchenau in Abh. Naturw. Ver. Bremen 7 (1880) 
32. 
Java, Forbes 104! Formosa, Oldham 881,637! Corea, Wilford 968! 
China, Maingay 170! 
India, Khasia Hills, 6,000 ft. alt.! Himalaya, 7,000 ft.! Sikkim 9,000 
ft.! Africa! Australia! 
Although Doctor Schinz and I have considered these all to belong to 
one species, at the present time I am in doubt as to whether or not this 
is true. The figure of the fruit given by Ascherson & Graebner 2 certainly 
does not belong to Potamogeton javanicus Hassk. but may have been 
drawn by mistake from P. orientalis Hagst. Hasskarl in his description 
says “fructus drupacei viridi subrotunda 3-cristata cristis lateralibus 
minus promunalis 2 gibbis, intermedia sinuata 3-4 gibba.” Buchenau has 
“Fructus dorso carinati, basi bituberculata”, and Mueller “carpi- 
dis dorso tricarinatus et repando-denticulatis.” 
But in the species of Potamogeton with tubercled fruits, the variation 
in this character is great; for instance the range of variation from P. tri- 
1 Engl. Pflanzenreich 31 (1907) 1-184. 
2 L. c. 47, fig. lit C. 
339 
