511 
or rarely 2—3 together, and have small zoospores. The thicker bran¬ 
ches are from 135 to 170^ thick. This plant undoubtedly comes 
very near A. albescens. 
Grows in sheltered localities between tide marks, and fruiting 
specimens were found in May. 
Found hitherto only on Strom 6: Kalbakfjord at the exit of a 
stream; Syd.: Tvseraa (!). 
188. A. flagellata Kjellm.? 
In figs. 104 and 105 I have given the illustration of an Acrosi- 
phonia , which has sometimes a few single fertile cells, sometimes 
up to 20 together in a continuous row. As shown in the figure 
the fertile cells are intercalary, and the zoospores small, hence the 
plant belongs to the sub-genus Melanarthrum Kjellm. The chroma- 
tophore is rather finely recticulate, with numerous pyrenoids (fig. 105 f). 
The thicker main branches are about 135 [a thick; growing shoots, 
particularly vigorous, attain to a thickness of some 120 fi just below 
