Contribution. I. 43 



is an intermediate one between f. litoralis and f. typica, yet 

 most likely to be reckoned to the latter. I therefore propose 

 to call the former f. Ejelhnani, and the latter I have called 

 f. typica [3 densa. The form Kjellmani, as already mentioned 

 by K j e 1 1 m a n, by a cursory examination reminds of Tt. 

 elegans, and sometimes grows jointly with this species. It 

 reaches a length of 8 cm. Rather similar to f. Kjellmani in 

 general habit and equal in size is f. typica ^ densa, which, 

 as above mentioned, also appears within the litoral zone, but 

 never jointly with, or as far as I have seen, on such loca- 

 lities as this one. It differs from f. typica a distans by being 

 somewhat tufted, though not always, and by its smallness 

 and far denser branching. Sometimes it becomes almost as 

 slender as f. Kjellmani. As for the structure too it is most 

 likely related to f. typica a distans, although I have not, in 

 this respect, seen any real limit between the forms of the 

 present species. Cp. Kjellm. N. Ish. Algfl. p. 221, t. 15, fig. 

 4 — 6. The form is generally litoral, pelagian and occurs 

 mostly in rock- pools within the lower part of the zone. But 

 it is also to be found in the upper part of the sublitoral 

 zone, on a depth of 2 — 4 fathoms, and here I have met with 

 every transition between this form and the for^n distans. I 

 have also seen this form from Marblehead, Mass., N. America. 



The form a distans is sublitoral as well as elitoral. It 

 grows in scattered individuals and chiefly on hard stony or 

 shingly bottom on open coast. But it has also been collec- 

 ted on looser bottom and in sheltered localities, though it 

 here never seems to thrive. Most vigorously developed it 

 appears on a depth of 8 — 15 fathoms on unsheltered coast. 

 In the elitoral zone I have found isolated specimens on a 

 depth of about 25 fathoms. 



The plant becomes never so large and luxuriant as the 

 preceding one. The largest specimens I have seen had a 

 length of about 25 cm., but it is commonly much smaller, 



