soaked in lactophenol, and the thickness of the frond was 39 fx. The 

 cells in the middle of the frond were nearly „fere quadraticae". Generally 

 I think that the formae of P. miniata are not distinguishable by the 

 shape of the cells in the middle of the frond, as I have seen, in the 

 same section, cells that were „quadraticae, fere quadraticae" and „vertica- 

 liter rectangulares " . 



f. amplissima (Kjellm.) K. Rosenv. grows in still water beneath 

 low-water-mark. At first it is attached to other algæ, but soon it be- 

 comes loose and its size increases. The largest collected specimen was 

 43 cm. long and 29 cm. broad. Specimens , which are folded in the 

 way described by Kjellman (The Algæ of the Arctic Sea) , sometimes 

 occur, but often they are not more folded than the f. typica. F. amplis- 

 sima is a form analogous to the great specimens of Monostroma fuscum, 

 which also are loose and grow at low-water-mark in quiet water, often 

 in company with the f. amplissima af P. miniata. In quiet creeks on 

 sheltered coasts these two species, Porphyra miniata and Monostroma 

 fuscum, when loosened from the substrata (algæ, stones, shells), to 

 which they are fastened, increase in size and lie loose on the bottom 

 of the sea. Such large specimina of P. miniata I call f. amplissima. 



Probably common round Iceland. 



E. I cel. common and abundant. 



N. I c el. Grimsey (O. D.) ; Eyjafjöröur. 



NW. I c el. Hrütafjöröur, Isafjöröur, Dyrafjöröur (G. 0.). 



SW. Icel. common. 



S. Icel. Vcstmannaeyjar. 



Porphyra coccinea J. Ag. 



Few, sterile specimina on Desmarestia aculeata in a depth of 6 — 10 

 fathoms. 



S. Icel. Vestmannaeyjar. 



Conchorelis rosea Batters, On Gonchocelis, a new genus of perforating 

 Algæ in G. Murray : Phycological Memoirs I. London 1 892. 



In the sublitoral region to a depth af c. 20 fathoms in Balanus, 

 Mya truncata, Gyprina islandica, Modiola, Astarte, Buccinum undatum, 

 and Serpula, and in the litoral region in Spirorbis on Fucus. I have not 

 seen the sporangia. In the inflated cells I have seen a distinct stellated 

 chromatophore. Mr. Nad son 1 ) thinks that Gonchocelis rosea does not 



: ) G. Nad son: Die perforierenden (kalkborenden) Algen und ihre Bedeu- 

 tung in der Natur, in Scripta Botanica Horti Universitatis Petropolitanae, 

 fase. XVIII. 1900. 



