253 



commonly proceed from the lowest cells in the branches and are often 

 just like hånds catching other filaments. Sometimes also the apices 

 of the branches terminate in such rhizoid-Uke branches (fig. 1 c 

 plate X); the cells in these branches do not contain so much chlo- 

 rophyl as the other cells. I have not found in this species any 

 differentiation of variously developed specimens such as is men- 

 tioned by Kjellman in his exhaustive description of the Ægagropila 

 canescens. 



The basal bodies of gonidial character described by Kjellman 

 also appear to be of but rare occurrence here. I have only once 

 seen some cells at the base of a filament which I thought were 

 identical with Kjellman's basal bodies (fig. 1 b plate X), they con- 

 sisted of two cells, the contents of which were dark-green and they 

 were distinguished by their rather thick walls. From both the 

 cells proceeded richly ramified filaments. 



Empty cells in the apices of branches have also generally been 

 found here as well as in the species examined bj^ Kjellman, but 

 if they are due to the formation of swarm-spores or are occasioned 

 by mere outer mechanical causes I cannot tell, at all events I have 

 not seen holes in the wall. 



The branches are sometimes opposite and sometimes spreading 

 and the ramification is altogether very irregular as the main filament 

 is often undeveloped. The cells are sometimes nearly cylindrical 

 and sometimes — and this applies parlicularly to the older cells 

 — inflated at the apex (Fig. 1 a Plate X). The thickness of the 

 cylindrical cells varies with an average of about 60 /a, the length 

 is about 5 — 10 times greater. The cell-walls of the older cells attain 

 rather a considerable thickness, up to 8 i^. 



If we now compare this Færoese species with those of Kjell- 

 man's in his above-mentioned work, I think it is nearest to Æga- 

 gropila Martensii. The specimens in Nordst. and Wittr. Exsic. No. 112 

 bear a very fair resemblance in habit to those from the Færoes, 

 but a closer examination shows some smaller differences of which 

 I shall especially point out that the cells of Æ. Martensii in N. and 

 W. Exs. are considerably more inflated, even the younger cells, 

 furthermore, that the cells are throughout proportionally shorter 

 and lastly that the cell-wall is considerably thicker than in the 

 specimens from the Færoes. 



As to the faet of my having seen among the Færoese specimens 

 an individual in the cænobium proceed from a basal body which 



