268 с. H. Ostenfeld. 



G. Karsten (1. с, p. 185) reports that be has found auxospores in 

 Cose, radiatus and Klebahn in Cose, exeentrieiis, but closer informa- 

 tions are not, as far as I know, given concerning the occurrence of 

 this phenomenon in the genus Coseinodiseus. 



Fig. 4. Coseinodiseus siibbuUens Jørg. 250 t. m. 



Cose, siibbiiliens was dominant in samples from Danmarks Havn 

 and from the coast water in 1906, 1907 and 1908 in July — September. 

 Few' living specimens were present in two samples from October 1906 

 taken in cracks in the ice of Danmarks Havn. In the pack-ice it 

 was very rare, only few specimens seen in a couple of samples. 



D i strib. According to Gran a boreal species occurring especialh- in 

 ttie regions where polar and atlantic currents meet, often in large quantities. 



12. Coseinodiseus marginatus Ehrbg., Abhandl. Berlin. Akad. 

 Wissensch., 1841, p. 142; A. Schmidt, Atlas Diatom.-Kunde, pi. 62, 

 figs. 1 — 5, 9 — 11; pi. 59, fig. 11; C. fimbriato-limbatus A. Schmidt, I.e., 

 pi. 65, figs. 3—6; pi. 113, fig. 2; C. limbatiis A. Schmidt, 1. c, pl. 63, 

 fig. 7; Ostenfeld & Paulsen, Medd. Grønland, XXVI, 1904, p. 160. 



Som few empty frustules of this coarsely areolated species were 



found in a sample from the outer part of the pack-ice in August 



1906. 



Distrib. Oceanic temperate species known from the plankton af the 

 North Atlantic west of 26° W. Long., not at home in arctic water. 



