M. Foslie. Eemarks on forms of Ectocarpus and Pylaiella. 



125 



ter, with rather thin walls. Most of the specimens collected 

 were sterile, some few ones are provided with terminate 

 sporangia. 



I also found other forms of Pylaiella at several places 

 in West-Finmarken most neetrly related to the last named 

 one, though often unlike as to the habitat and sometimes 

 with thicker cells, but almost fully agreeing as to the 

 ramification. They are, however, sterile. 



A small specimen of the named alga collected at 

 Tromsø in a rock-pool at high-water mark is richly provi- 

 ded with sporangia. These are mostly terminate, 1 — 10, or 

 sometimes until 18 eontinuous, and not seldom divided by a 

 longitudinal wall into 2 daughter-cells. 



At Skorpen in the northern part of Tromsø amt I met 

 with an interesting form living on the bottom of shady rock- 

 pools in the lower part of the litoral zone. It forms loose- 

 ly entangled tufts with most of the branches opposite but 

 almost ever issuing under a rigth or nearly rigth angle. It 



* • 



was, however steril, so that I am not sure to which spe- 

 cies or form it is to be referred. It has the habit of P. li- 



toralis f. compacta. 



I found last summer at Kvalsund in West-Finmarken 

 a form of Pylaiella varia which is in some respects nearly 

 connected with one of the above mentioned forms of P. li* 

 toralis f. compacta. It forms small tufts until 16 cm. long 

 composed of numerous, narrow bundles lying loose on the 

 bottom on a depth of 6—8 fathoms. The colour is light 

 olive brown. The long branches most often issue 2—3—4 

 in xramber from adjacent cells, and the short branches cha- 

 racterizing P. varia are much fewer than quoted by Kjell- 

 raan in N. Ish. Algfl. p. 348, of about the same number as 

 the long banches, or sometimes even fewer. The cells are 

 40 a thick, 7*— 2 times the diameter in length, with thin 



