60 



but judging by the stages of division of the sporangia shown 

 in ßg. 9 c, the number of the spores is at least 8. 



The species is nearly related to U. pseudoflacca but differs 

 from it essentially by the peculiar shape of the basal cell and 

 the occurrence of rhizoids. The frequent constrictions of the 

 filaments may be regarded as another difference, probably less 

 important. 



The species was collected in the littoral region in July 

 — August, with unripe sporangia in July. 



Gr. occ. : Umanalik east of Kangek 0, 60° 36', a rock near Kaer- 

 sok, 60° 29', the south side of Tusardluarnak, 60° 7' (A. Jessen). 



99. I. consociata Wille Studien p. 25. 



To the typical form of this species I have referred some 

 specimens collected by L. K. Rosen vinge at Godthaab. in 

 rock-pools near high-water mark. The specimens occurred in 

 company with blue-green algae and some green algae resembling 

 stages of Pleurococcus. The filaments are 7 — \0 /j. thick, and 

 the length of the cell is varying from V4 of the breadth to 

 about as much as the breadth. Well developed rhizoids occur. 

 The filaments are considerably narrower than in the Norwegian 

 plants, and probably the specimens may be regarded as a 

 f. minor. 



Specimens collected by Jessen in the littoral region at 

 Umanalik seem to be fully identic with Wi lie's species. The 

 filaments are 14 — 22 /i thick, and the length of the cell varies 

 from about Va to '■^U of the breadth. Rhizoids are abundant, 

 and coalescent filaments have sometimes been met with. Fila- 

 ments, that were indistinctly narrowed at intervals, occasionally 

 occurred. 



Gr. occ: Godthaab (L. K. R.) ; Umanahk (A.Jessen). 



var. islandica Jönss. icel. Alg. p. 354, U. implexa K. Rosenv. 

 Grl. Havalg. p. 936 ex parte. 



Typical specimens of this variety have been collected by 



