— 157 — 



f. pygmæa is only known from : 

 SW. I cel. Viöey. 



Ectocarpus siliculosus (Huds.) Lyngb. Hydr. Dan. p. 131, Kjellm. 

 Handbok p. 78, Kuck. Ectoc. p. 15. 



This species occurs in the litoral region on other algæ e. g. Chordaria 

 flagelliformis, Chorda Filum, Scytosiphon lomentarius, and in the sublitoral 

 region down to a depth of 4 fathoms on Saccorhiza dermatodea and spe- 

 cies of Laminaria. Gathered with plurilocular sporangia in April and 

 June — August. The Icelandic specimens agree well with the typical form. 

 The thickness of the main branches is from 50 p— 60 fi in the middle, 

 but upwards and downwards the filaments become narrower. Sometimes 

 the filaments are here and there surrounded by a mantle of rhizoids. 



Probably common. 



N. I cel. Eyjafjöröur. 



NW. I cel. Hrütafjöröur, Kollafjöröur. 



SW. I cel. Melar, Skögarnes, Viöey. 



Ectocarpns penicillatus (Ag.) Kjellm. Handbok p. 76; E. confervoides 

 f. penicillata Kjellm. Bidrag p. 79. 



I have met with this species here and there, growing on other algæ 

 e. g. Scytosiphon lomentarius in the litoral region and on Alaria esculenta 

 and Laminaria digitata in the sublitoral region down to a depth of 2 

 fathoms. 



E. Icel. Berufjöröur, Seyöisfjöröur. 

 N. Icel. Gn'msey (O. D.); Eyjafjöröur. 



SW. Icel. Grnnsey in Hvammsfjöröur , Stykkishölmur ; Hvalfjöröur 

 (Grönlund) ; Reykjavik. 



Ectocarpus fasciculatiis (Griff.) Harv., Kjellm. Handbok p. 76. 



I have met with this species in the litoral region growing on other 

 Algæ e. g. Rhodymenia palmata, and in the sublitoral region on lamina 

 and stipe of species of Laminaria and on Alaria esculenta. At Vest- 

 mannaeyjar it often occurred gregariously on Laminaria digitata f. steno- 

 phylla. It has been gathered with plurilocular and unilocular sporangia 

 in May — July. Both kinds of sporangia are sometimes to be found in the 

 same specimen. As a rule the unilocular sporangia are, as the plurilocular 

 ones, unilaterally situated on the upper side of the branches, especially 

 in the middle branches. They are sometimes exceedingly dense and are 

 somewhat resembling the sporangia of E. pycnocarpus Rosenv. (Grl. Havalg. 

 p. 886, fig. B and C) and agreeing with the figure given by Börgesen 

 (Eær. Alg. p. 411, fig. 71, a). In the lower part of the main axis I have only 

 seen some few and scattered sporangia and towards the apex they also 



Botanisk Tidsskrift, 25. Bind. 



