On the Marine Algæ from North-East Greenland. 121 



wardly, a result of the growth of the sporangium and the surroun- 

 ding cells after the formation of the former and often combined 

 with cell-divisions of the latter (fig. 7 B, D). Strange to say, the 

 zoospores had not developed normally but had formed a cell wall 

 without having been set free, and the older sporangia thus became 

 filled with closely packed polygonal cells, which gradually became 

 rather poor in contents and might sometimes suggest the structure 

 of plurilocular sporangia (fig. 6, C). Not seldom the older sporangia 

 are open and the cells derived from the abortive zoospores are 

 prominent above the surface of the frond (fig. 6, D, E), but normally 

 developed and emptied sporangia have not been met with. Some- 

 times the zoospores do not fill the sporangium but leave an empty 

 place in the middle of it (fig. 6, D). It may also happen that the 

 upper part of the cell has not participated in the formation of 

 zoospores. 



Notwithstanding that this species differs from the other hitherto 

 described species of the genus Punctaria by the want of hairs, I 

 think it unnecessary to remove it from that genus. It is noteworthy 

 that two other arctic members of the same family are also entirely 

 devoid of hairs, namely Omphalophijlhim iilvaceum and Phœosaccion 

 CoUinsii. Gathered in the end of August and the beginning of September. 



Loc. Along Koldewey Island; Danmarks Havn; Baadskæret; bay off 

 Vesterdalen, 4 to 11 meters depth. 



Omphalophyllnm K. Rosenv. 



35. O. ulvaceum K. Rosenv. 



K. Rosenvinge (1893) p. 873, (1898 I) p. 73; Jonsson (1904) p. 34. 



The collection contains a large specimen of this arctic species, 

 no doubt the largest hitherto found; it measures 28 cm. in greatest 

 diameter, 16 cm. in greatest radius. It was sterile in the beginning 

 of September. A small fragment without indication of locality was 

 also sterile. 



Loc. Along Ivoldewey Island. 



Fam. Elachistaceœ. 

 Elachista Dub. 



36. E. fucicola (Veil.) Aresch. 



K. Rosenvinge (1893) p. 878, (1898 I) p. 74; Jonsson (ИЮ4) p. 35. 



A few specimens occur attached to Halosaccion ramentaceiim 

 and Punctaria glacialis. They belong to the f. typica and had unilo- 

 cular sporangia in August. 



Loc. Bay off Vesterdalen. 



