396 



I cannot exactly sav, but it mav doubtless be presumed to grow 

 at a height of several metres, more particularly in tbe interior of 

 the large caves which occur so frequently along the exposed coasts 

 of the Færoes. Thus, I saw in one of the large caves (at least 20 

 metres high) at Troldhoved, large, reddish-purple patches, far up 

 on the walls and on the roof of the cave, which were undoubtedly 

 this alga; in a small cave near Kvalbo on Sydero it occurred as a 

 dense covering on the roof which was just within reach. 



In the sublittoral zone I have only found it epiphytic on La- 

 minaria, but Kjell man says that in the Polar Sea he came across 

 it in the latter zone both on stones and algæ. It has been found 

 down to a depth of some 10 fathoms. 



I found a small number of specimens in June and July which 

 were still bearing a few tetraspores, but the greater part of them 

 had fallen off. The rest of the specimens gathered from April to 

 August were sterile. On the other hånd, specimens rich in tetra- 

 spores were found in November and December. Thus, as along 

 the Danish coasts so also along the Færoes the period of fructifi- 

 cation falls undoubtedly during the winter months, though the alga 

 is sometimes found bearing tetraspores far into the summer. In 

 Iceland Jonsson found a few tetrasporic specimens in the spring 

 and summer; and Kjellman is of opinion that at Spitzbergen the 

 tetraspores are formed in May and June. 



The frequent occurrence of this species along the Færoese coasts 

 was also noted tw Lyngbye, who writes: — »Habitat ad rupes abruptas 

 insularum Færoensium in summo refluxus limite, copiose; imprimis 

 autem ad stipitem Laminariæ digitatæ. ibidem«. 



64. Rh. seiriolanum H. Gibson. On the Development of the Spo- 

 rangia in Rhodochorton Rothii Niig., and Rh. lloridulum Nag., and 

 on a new Species of that Genus (Journ. of the Linnean Society. Bot. 

 vol. 28, 1891, p. 204). 



Only a small quantity of this species was found epiphytic on 

 Ceramium acanthonotum associated with Chantransia secundata. It 

 occurred on exposed coast near high-water mark. 



Tetrasporic specimens occurred in April. 



Found hitherto only on Str. : Velbestad (!). 



