162 



region. In the former I mostly met with it fastened to Mytilus 

 shells or occasionally stones in deeper rock-pools, but apparently 

 not to the rock itself. In the latter region it also most frequently 

 fastens itself to smaller or larger stones, more seldom to rocks, 

 and, so far as I have seen, nearly always to be found only on 

 stony bottom. It prefers exposed places, and here it grows in 

 rock-pools or on a depth of 1 — 2 fathom, but in more sheltered 

 localities it always appears to descend farther down, to a depth 

 of about 10 fathom, seldom more, and to be found in by far 

 smaller numbers than in the former. However, it does not pene- 

 trate far up the fjords. The development of sporangia probably 

 takes place nearly all the year. Thus I have collected specimens 

 from the middle of May to the middle of September with partly 

 emptied conceptacles or scars after older ones nearly effaced by 

 new-formed tissue partly with ripe sporangia or such being in 

 development. 



Occurrence. It appears to be commonty dispersed along the 

 whole coast of Finmarken and is found eastward to Kjelmø in 

 Sydvaranger, at several places abundant, for inst. Mehavn and 

 Kjøllefjord in East-Finmarken, Heines, Kjelvik, Skarsvaag and 

 Loppen in West-Finmarken. It has not with certainty been found 

 farther to the south than Skorpen (Kvænangen) in Tromsø Amt. 



Geogr. Distribution. Iceland (S trom fe It), Grønland (Ro- 

 sen vinge). 



Lithothamnion coalescens Fosl. mscr. 



L. fronde crustacea, subarcte adnata, superficie plus minusve 

 inæquali, striis brevibus, densis, radiatim et concentrice dispositis,. 

 1 — 1.5 mm. crassa, dilute vinoso-purpurea; crustis plerumque com- 

 pluribus demum confluentibus, margine crenato-lobato ; concepta- 

 culis sporangiferis sub foveola leviter excavata 80 — 100 fi lata 

 immersis, diametro 200 — 300/^-; sporangiis binas sporas foventibus,, 

 150—200 fi longis, 60-80 /z latis. Tab. 19, fig. 15—20. 



Description of the spedes. The plant forms more or less 

 irregular crusts on smaller stones. Several crusts frequently are 

 founded on one and the same substratum, but in their farther 



