IX, ©, 4 Bennett: Potamogetons of the Philippines 343 
CorEA, Faurie 224 (1906); JAPAN, many localities; CHINA, Chihli, David 
1916. Also in Europe, Africa, and North America, but not recorded from 
Australia, New Zealand, or Polynesia. 
*13. POTAMOGETON PERVERSUS A. Benn. sp. nov. 
Caulis simplex, 1.5 ad 2.5 dm altus. Folia submersa inferora 
1 dm longa et 1 ad 3 em lata, 11-nervia, basi et apice angustata ; 
superiora lanceolata vel ovato-lanceolata. Folia natantia ovata 
vel ovato-lanceolata, basi angustata, 13- ad 16-nervia, ca. 7 cm 
longa et 3 cm lata, coriacea, longipetiolata (ca. 4-10-5 cm 
longa). Stipulae deciduae. Pedunculi 5-7 cm longa. Spicae 
2-8 cm longae, densae. Fructus semi-obvali, ventre convexae 
cum bulla centralis, dorso semicircularis, carina media subacuta, 
lateralibus indistinctus, carinae intermedius striatus, drupa com- 
pressa cum dua bulla, bullae connectiva cum striae. 
Habit of the European P. polygonifolius Pourr., but the fruit very 
different. Four habitats in Australia given for P. Tepperi must for the 
present remain uncertain as there is not sufficient material to say to which 
of the two species, now separated, they belong; but Mr. Tepper’s original 
specimens are well matched by the Philippine ones, and this material also 
shows more definitely the lower leaves. For some time I have realized that 
two species have been confounded under P. Tepperi, but the want of 
fruiting specimens with so many so-named, especially the Japanese spec- 
imens, has been a bar to separate them. But keeping to the original 
specimens from Mr. O. Tepper, it proves to be a far rarer species than 
I had supposed, while the numerous other specimens placed under it seem 
to conform to one general type, and I now make this a separate species. 
P. Tepperi seems to be one of the species that by their much thickened 
leaves, form a small section of the genus nearly confined to Australia, but 
occuring in Malaya, and more rarely in China; with perhaps an outlier in 
Mauritius, but the specimens from Mauritius are too poor to so refer with 
any certainty. Many Australian specimens want the lower leaves, hence 
they have been simply referred to P. natans, although in fruiting char- 
acters they are not allied to that species. Gradually as more perfect 
specimens are collected we shall be able to deal with them in a more 
definite manner. 
An extension of this species may eventually have to be made to North 
America. Dr. Morong, Bull. Torr. Bot. Club 13 (1886) 145 describing 
P. Curtissiti from Florida remarks: “Mr. Curtiss also sent what appears 
to be a peculiar form of P. natans. It looks exactly like specimens in the 
Torrey herbarium* from India, which are labelled P. natans var.” These 
are Hooker and Thompson’s Khasia Hills plant and are P. perversus ! 
And I believe that Dr. Small’s P. Floridanus* is the same plant, but in 
writing to Dr. Small he told me that there were no duplicates; so it must 
remain an open question until specimens can be compared. 
Distribution: CHINA, Pekin, Bretschneider 778! Ichang, Henry 2366, 
* Bull. Torr. Bot. Club 13 (1886) 156. 
‘Fl, S. E. U. S. (1903) 37. 
