550 



material which I have examined. Other marine forms are gene- 

 rally not common, and usually occur dispersed in the gatherings, 

 the only exception being a gathering labelled: -- »Delesseria san- 

 guinea (L.) Lam., Skaalefjord (Ostero)« in which I observed some- 

 thing like 40 species, almost all of which were marine forms. 

 Plankton-forms snch as Chætoceros and Rhizosolenia occur in soli- 

 tary specimens, and nsnally in fragments only. 



In localities which may more parlicularly be characterized as 

 »exposed to the open sea« I have found the fol lo wing charac- 

 teristic species: — 



Viderejde (Videro) 1 gathering Gomph. pachycl. 



Gjov (Ostero) 3 Frag. striat., Gomph. kamtsch. 



Molen (Ostero) 2 Syn. inv. 



Saxen (Stromo) 1 Achn. subsess. 



Hojvig (Stromo) 1 Syn. aff. pa.ru. 



Kvivig (Stromo) 13 Cocc. sent., Frag. striat., Gram. mar., 



Isthm. neru., Syn. inv. 

 Vaago, north side 2 Gomph. pachycl, Licm. angl. 



Troldhoved (San do) 2 Cocc. scut. Gomph. kamtsch S: Aest., 



Gram. mar., Syn. inv. 

 St. Dimon 2 Isthm. nerv., Licm. Oedip. 



Famien (Sydero) 1 Achn. parv., Syn. aff. parv. 



Vaags Ejde (Sydero) 8 Gomph. kamtsch., Licm. angl. S: 



Oedip., Striat. delicat., Syn. inv. 

 Sumbo Holm 1 Licm. angl., Syn. inv. 



True Polar forms did not occur, but I found some 50 fresh- 

 water forms, the latter were always met with in solitary examples 

 and excepting a very few species (e. g. Diploneis Boldtiana), were 

 already known as belonging to the freshwater algæ of the Færoes. 

 They occurred most abundantly in the gathering from Kalbakfjord 

 (Stromo), doubtless because the circumstances that prevail there 

 are such that the Diatoins are not immediately carried away by 

 the stream or the waves, but remain hanging to the algæ. I have 

 not found Snrirella Moelleriana, so it must undoubtedly be a fresh- 

 water form. 



With regard to the charaeteristic genera, there is on the 

 whole no slight resemblance between the present material and the 

 coastal Diatoms of Greenland, with the exception that Gom- 

 phonema and Grammalophora are more conspicuous along the 



