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viously known only from Ceylon where Leu duge r-Fortm ore! 

 has found it in a sample ^recueillie .... sur l'ancre d'un navire 

 mouillé, par huit brasses d'eau, à Colombo, sur les côtes de 

 Ceylan". Certainly 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 Ach. brevipes. 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 freshwater 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 the 

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

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

 hyalina (Australia), Cymbella japonica (Japan), Eunotia major octo- 

 undidata (Banca), Desmogonium Babenhorstiantim (Banca and China), 

 Denticula Van Heurckii (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: Cymbella, 

 Epithemia, Cyclotella, Surir ella, Fragilaria, Denticula and wanting 

 are: Pleurosigma, Rhoicosphenia, Cymatopleura, Tabellaria, Diatoma, 

 Meridion, Melosira. 



