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viously known only from Ceylon where Leiiduger-Fortmorei 

 has found it in a sample „recueillle .... sur I'ancre d'un navire 

 mouille, par huit brasses d'eau, a Colombo, sur les cotes de 

 Ceylan". Certainlv there is nothing to prevent that, at Colombo 

 it might have been carried out into the sea with freshwater; 

 however the whole habit of this species does not at all agree with 

 Achnantheae from freshwater, but much more with marine forms 

 such as Aclt. hrevipes. Perhaps the examination of the marine 

 Diatoms collected by the Danish Expedition will prove that it also 

 occurs in the Gulf of Siam, but its presence in elevated inland 

 waterfalls is nevertheless very strange. 



As to the general character of the flora so far as we can 

 judge from the present samples of fresliwater Diatoms, we must 

 say that it is less pronounced by the present than by the wanting 

 forms. Most of the species observed occur scattered round tlie 

 world, a few have previously been recorded only from more adja- 

 cent localities e. g. Navicula Stodderi (Bengal), Stauroneis anceps 

 hyalina (Australia), Ci/nibella japonica (Japan), Ettnotia major octo- 

 imdidata (Banca), Desmogoninm Bahenhorstianum (Banca and China), 

 Denticida Van. Henrckii (Japan) but none of those species occurs 

 in such a quantity that it might be said to characterize the collec- 

 tion in its entirety. The following genera are however either very 

 sparingly represented or they occur in not typical species: Cymhella, 

 Epitliemia, Ct/clotella, SurirelUt, FragUaria, Detdicida and wanting 

 are: Pleurosiijma, Bhoicosphenia, Cymatopleura , Tahellaria, Diafoma, 

 Mei'idion, Melosira. 



