400 



Order CORALLINACEAE. 



PHYMATOLITHON 1 Fosl. 



71. Ph. polymorphum (L.) Fosl. 



As in the Arctic Sea, according to Kjell man (N. I., p. 135 [102]) 

 so also in the Færoes this species grows in the littoral zone, where 

 it occurs abundantly; but it is also met with in the sul)littoral zone 

 down to a depth of 10 fathoms. Its proper habitat is near low- 

 water mark or strictly speaking on either side of low-water mark, 

 where it occurs especially on smooth, vertical rock-faces as a thick 

 crust, varying in colour from white to pink and forming a belt 

 often several feet in breadth. It grows most luxuriantly in the 

 interior of caves and occurs liere from a height of several feet 

 above sea-level downwards into the water as far as the eye can 

 see. According to my observations this species extends farthest into 

 the caves, up to the point where they become too dark even for it. 



According to what Mr. Foslie writes to me it bore sporangia 

 in May, July and December. 



This species is extremely common along the Færoese coasts. 



72. Ph. lævigatum Fosl. 



Found in the sublittoral zone down to a depth of 10 fathoms 

 on stones and shells. It has been observed both in sheltered loca- 

 lities and in the open sea. 



According to Mr. Foslie it bore sporangia in July, October and 



November. 



Vid.: Kvannesund (H. J.); Bordo: Haraldsund (!); Kuno (H. J.); 

 Ost.: Glibre (H. J.); Str.: Arge (!), Sundene between Thorsvig and Kval- 

 vig (!); Syd.: Vaagfjord (H. J.). 



CLATHROMORPHUM Fosl. 



73. Cl. circumscriptum (Stromf.) Fosl. 

 Bore young sporangia in June. 



Found once only on Str.: in Sundene between Thorsvig and Kvalvig (!). 



LITHOTHAMNION Phil. 



74. L. glaciale Kjelbn. 



According to Mr. Foslie all Ibe specimens are young and partly 

 stunted hence the determination is open to doubt. 



1 Mr. M. Foslie of Trondhjem has kindly determined tliis genus and the 

 ollowing: — Clathromorphum, Lithothamnion, Lithophyllum and Dermatolithon. 



