78 M. FOSLIE. [1905 



annular border, 150 — 300 /x in diameter. The roof is intersected 

 with 30 — 70 muciferous canals. The sporangia are four-parted, 

 80 — 110 jx long and 25 — 45 \x broad. Along the northern part 

 of the coast of Norway a form is rather frequent whose concep- 

 tacles are slightly elevated above the surface of the plant and re- 

 semble those mentioned below under Ph. investiens f. torosa, which 

 I suppose are not normally developed. Besides there are some- 

 times found conceptacles with peculiar disc shaped local formations 

 of tissue like those mentioned below under Ph. Icevigatum. The 

 conceptacles of cystocarps are at first convex, however frequently 

 at length resembling those of sporangia and of about the same 

 size with a single central pore. The conceptacles of antheridia 

 resemble those of cystocarps in shape and are 100 — 120// in dia- 

 meter. Overgrown conceptacles are frequently numerous in a 

 section, but they are often wholly or in part filled with new- 

 formed tissue. 



Ph. polymorphiwi occurs most numerously in the lower 

 part of the litoral zone and in the upper part of the sublitoral 

 zone. According to Borgesen, it is found at the Faeroes 

 even above the highest water mark. On the other hand, it 

 descends to a depth of 5—6, sometimes to a depth of about 

 10 fathoms, and on the northern coast of Norway (West Firi- 

 marken) I sometimes even found it at the depth of 15 fathoms. 

 At Morocco and at a single place in the Adriatic it has been found 

 very scantily at a depth of 8 — 17 fathoms. Particularly in the 

 sublitoral region the alga forms the substratum of a large number 

 of other algae, e. g. Maria, Laminaria. At the same time it is 

 much attacked by boring algae and peculiarly by lower animals, 

 e. g. boring mussels, which often cause that the alga — chiefly 

 when growing old — is wholly or partly detached from the sub- 

 stratum. The species develops reproductive organs at any time 

 of the year in the areas from Finistere northward (except perhaps 

 Finmarken), but on the other hand also sterile specimens are met 

 with at the same times. 



Area: Norway: From Havningberg near Vardo in East- 

 Finmarken southwards (!); Sweden: West coast (Areschoug and 



