176 



of various kinds, biit appears to prefer solid rock or shirigle. In the Norwegian Polar 

 Sea it belongs to the so-called arctic formation, in the arctic region proper it forras a 

 common element of the Corallineacsa-formation, although it is not wanting in other for- 

 mations. Here it occurs sometimes gregarious in large masses. It prefers exposed 

 coasts and in the glacial part of the Polar Sea seeras not to enter into the interiör of 

 deep bays. However, on the north coast of Norway I have found it in the interiör of 

 Altenfjord. On the north coast of Spitzbergen it is found in full vigour throughout 

 the year, developing plenty of propagative organs in winter. During this season I have 

 found individiials with tetrasporangia in November, December, January, February, and 

 March; individuals with sporocarps have been met with in November in plenty and in 

 December. Besides, specimens with tetrasporangia have been observed on the coasts 

 of Spitzbergen in June, July, August, and October. At Nordlanden individuals with 

 tetrasporangia and sporocarps have been collected in July and August, on the coast of 

 Finmarken in August; on the west coast of Novaya Zemlya specimens with sporocarps 

 have been taken in July, with tetrasporangia in June and July. 



The form litoraMs belongs to the litoral zone, as is designated by the name. It 

 grew together with Ptilota elegans on the sides of a shallovv, grotto-shaped cavity in 

 a rock. 



Geoijr. Distrib. The present species seems to have its maximum of frequency in 

 the Greenhind Sea. It grows here where so ever the locality is suitable, in great nurabers 

 and with large, luxuriant individuals. It is common also on the coasts of Novaya 

 Zemlya, although not so much so as in the Greenland Sea, being replaced in the former 

 region by Pt. plumosa. On the coast of Finmarken and at Nordlanden it is dccidedly 

 more scarce than Pt. plumosa, contrar)^ to what seems to be the case in the White 

 Sea. The most northerly place where it has been found up to the present time, is 

 Treurenberg Bay on the north coast of Spitzbergen, Lat. N. 79° 56'. It is not known 

 from the Siberian Sea. 



Localities: The Nonoeginn Polar Sen: Nordlanden, common, according to Kleen; 

 Finmarken at Maasö, Gjesvasr, the south coast of Magerö, Talvik, local, but pretty 

 plentiful. 



The Greenland Sea: the east coast of Greenland; on the coasts of Spitzbergen 

 common and abundant. 



The Murman Sea: the coast of Russian Lapland; on the west coast of Novaya 

 Zemlya and Waygats from Matotshin Shar to Jugor Shar common, but less abundant. 



The White Sea: common and abundant. 



The Kära Sea: on tlie east coast of Novaya Zemlya, scarce. 



The American Arctic Sea: taken by Richardson, according to Harvey. 



Baffin Bay: Cumberland Sound, pretty common; the west coast of Greenland al 

 Tessarmiut, Neuherrnhut, Godthaab, Sukkertoppen, Holstenborg, Claushavn, Jakobshavn, 

 Godhavn, Rittenbenk. 



The herbarium of the Copenhague Museum contains several specimens of this 

 species without n.nj localitj' heing noted. The form integerrima is known to me only 



