316 



Ove Paulsen. 



This species of which fig. 

 16 gives some outline-figures, 

 was very common in Aug. 1908 

 in the sea outside the ice. In 

 the pack-ice and the coastal 

 water in 1908 it was scarce 

 though found in several samples. 

 In Danmarks Havn and in the 

 pack-ice and the coastal water 

 in 1906—07 it was rare and 

 occurred always as dead spe- 

 cimens. 



Distrib. Arctic oceanic spe- 



Fig. 16. Ccratium arcticum, different cells. 94 t. m. 



Apodiniiim Chatton. 



26. Apodinium(?) Chaetoceratis n. sp. 



Cellulae globosae niicleiferae membrana cellulosoidea tectae, ad 

 setas Chaetoceratis borealis appendicula adharentes et membranam ejus 

 perforantes: parasitiis igitur plasma hospitis exbaiiriens. Divisionibus 

 cellulae binae et qiiaternae nascuntiir. Long. cell. ca. 13 — 25 гл. Hab. 

 in mare gelido ad oram orientalem Groenlandiae. 



Dr. Ostenfeld who has worked out the Diatoms and Flagel- 

 lates of the present samples before I got them for investigation, 

 called my attention to this organism which he had examined be- 

 lieving it was a Diatom. But as the wall gaл^e cellulose-reaction 

 with chloriodide of zinc and as it w^as without silicium he saw it 

 would be nearer a Dinoflagellate than a Diatom, and he gave me 

 his drawings and notes. 



Once only I have found a cell of Apodiniiim Chaetoceratis upon 

 an awn of Chaetoceras decipiens, all other specimens seen were 

 fixed on the awns of Ch. boréale. Whether this is because the 

 awns of Ch. boréale are set with fine hairs I cannot tell with cer- 

 tainty, I have never seen the cells spit upon the hairs or otherwise 

 fixed to them. But it seems likely that awns set with setae atïord 

 better chance for fastening than smooth ones. How the cell is fixed 

 to the awn is difficult to discern. Fig. 17, С and D show a little 

 process by aid of which the cell is fixed. In other cases it seems 

 that there are two processes. Fig. F shows a cell made pellucid 

 by aid of Eau de Javelle, and on both sides of the awn is seen a 

 thickening not belonging to the awn but to the Apodinium. Fig. I 

 (drawed by Ostenfeld) shows tw^ cells in a mucilage which is 



