36 M - Foslie. 



developed on rock-slopes at exposed places. Often it also is 

 to be met with in rock-pools between tides. I do not know 

 how far down it descends into the snblitoral region. The 

 species probably develops its reproductive organs both in 

 summer and in winter. In summer it is often found with 

 the prolifications fallen off. Specimens with tetraspores have 

 been collected in June, July and August; at West-Finmarken 

 in May, June, July and August; and in Tromso amt in July 

 and October. 



Distribution: Common and plentiful almost everywhere 

 especially along the open coast. 



Halosaccion pubescens nob. 



H. thallo eramoso, subterete, apicem versus obsulote at basim ver- 

 sus valde et longe attenuato, subcartilagineo, prolificationibus simplicibus 

 vel irregulariter romosis brevissimis undique dense obsesso. Tab. 1 et 

 tab. 2, fig. 1. 



Syn. Halosaccion ramentaceuni Fosl. berb.; ex parte. 1 ) 



The species sometimes grows isolated, or more common- 

 ly several individuals rise from the same callus. The simple 

 frond is after its whole length, except the lowest part, very 

 densely covered with short simple or irregularly branched 

 prolifications, and getting gradually shorter towards the top. 

 These produce the tetrasporangia. Cp. pi. 1, the three figures 

 to the right. The figure to the left shows a specimen, the 

 prolifications of which for the greatest part are fallen off. 

 By a cross section of the lower part of the frond, the cells 

 of the outer layer are ordered in more or less regular series, 

 being vertically rectangular with acute or rounded corners, 

 more seldom squarish or roundish. The outermost cells are 

 most often larger than the inner ones. In this manner it 

 differs from other arctic species of the genus. Cp. Stromf. 

 Isl. Algfl. p. 30. 



') By tbis synonyme I only want to denote, tbat I bare distributed some 

 specimens of tbe present species under this name. 



