228 



Ernst Østrup. 



(2) From W. Greeiil. only, and from nowhere else 



in the Arctic districts 10 (5.5 ^/o) 



— E. Greenl. -j- E. of Greenl. only, and from 



nowhere else in the Arctic districts. . 15 (8.2 '^/o) 



— East Arct. S. only, and from nowhere 



else in the Arctic districts 19 (10.4 -Vo) 



(3) From W. Greenl. + E. Greenl 53 (29.1 ^'/o) 



— W. Greenl. + Eastward 90 (49.5 ^/o) 



— Eastward on the whole 149 (81.9 ^/o) 



These three percentage tables show, that there is a rise in the 

 percentages as regards the eastern districts, and therefore the Diatoms 

 found in the material at hand indicate an easterly tendency as 

 regards their Arctic distribution. 



As the material examined consists partly of Alga-samples, partly 

 of ice-samples, I have in the following table given an account of 

 the occurrence of the genera in these samples. 



Predominant in 



the Alga-samples 



are tiie genera 



Predominant in 

 the ice-samples 

 are the genera 



«4-. 'П 



о « 

 u > 



•2 = 



с ce 



Z-2i 



In both Alga- and 

 ice-samples oc- 

 cur the genera 



СЯ 4) 



л с 



f4 æ 



а Си 

 <! се 



И) 



— о 



'S ^ 

 о с 



CQ л 



Achnanthes .... 

 Amphipleura. . . 



Amphora 



Auricula 



Biddulphia .... 

 Campylodiseus . 



Cocconeis 



Grammatophora 

 Hyalodiscus. . . . 

 Licmopliora. . . . 

 Plagiogramma. . 

 Pleurosigna .... 



Podosira 



Rhabdonema. . . 

 Rhoicospenia. . . 



Surirella 



Synedra 



Trachyneis 



Tropidoneis .... 



Actinocyclus . . 

 Ampliiprora . . 

 Rhizosolenia . . 

 Stauroneis . . . . 

 Stephanopyxis 

 Thalassiosira . . 



10 



Caloneis 



Chætoceros . . 

 Coscinodiscus 

 Diploneis . . . . 

 Fragilaria . . . . 

 Gomphonema 

 Gjrosigma . . . 

 Hantzschia . . . 



Melosira 



Navicula 



Nitzschia . . . . 

 Pinnularia . . . 



103 



2 

 25 

 14 



3 



60 



1 



18 



3 



3 



35 



