KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 61. NIO Ii. 



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lamina appears rather like the intercalary meristematic zone in the Laminariacese. 

 The holdfast is solid and hooflike and very unlike the mäss of hapteres in Lessonia. 

 During my visit to South Georgia in April, 1909, I had not enough alcohol at 

 my disposal for the preservation of such large sea-weeds as Ascoseira, a complete 

 mature specimen measuring several feet in length. Unfortunately, I did not simply 

 dry the plants but put them into formaline. On my return home, all the other 

 material treated in this manner vvas found to be in very good condition, but Ascoseira 

 had been entirely spoilt, its tissue getting so brittle that the plants could not be 



Fig. 19. Ascoseira mirabilis; a cross section X (>0; b length section, X 85. — Photo. Prof. O. Juel. 



handled vvithout falling to pieces. Some material was treated with fixing solutions. 

 The result is not very good, and all the conceptacles are mature. Still, I am able 

 to complete my earlier observations. The long hairs found in the conceptaele (see 

 fig. 20 a, f) are not grouped together in the centre but scattered along the bottom 

 and walls. I still believe that the conceptaele starts as a hair-pit — sterile crypto- 

 stomata have not been observed — gradually getting deeper and larger; the final en- 

 largement is due to the enormous produetion of »sporangia», which fill the concep- 

 taele pressing together the surrounding tissue, the cell-walls becoming stretched in 

 tangential direction and much torn. If two conceptacles stånd opposite each other, 

 what frequently nappens, the tissue between them becomes quite squeezed (fig. 19 a). 

 Some new observations were made on the reproduetive bodies. By searching 

 the basal parts of the long chains some younger stages were observed, which show 

 the origin af the 8 »spores> better than before. The nucleus and protoplasm of the 

 mother cell are divided three times, resulting in 8 portions, each with its nucleus 

 (fig. 20 c, d). Such stages remind us of the oogonia in the Fucaceae, where, in some 

 cases, distinct plasma lamellae separate the eggs. But in Ascoseira a simultaneous 



