KONGL. SV. VET. AKADEMIENS HANULINGAR. BAND. 20. N:0 5. 189 



afterwards mqistened specimens. Antheridia and sporocarps are sometimes, but appa- 

 rently not always, developed on the same individual. The development begins at the 

 margin, proceeding inwards. Of two cells in the same cross section either both may 

 be developed into antheridia or sporocarps, or the one may become an antheridium, the 

 other a sporocarp (fig. 7 — 8). The sporocarps contain only few spores. 



Habitat. It grows, when attached, sublitoral, and usually scattered in 2 — 3 fathoms 

 water. I have never found it but on exposed coasts. Specimens with sporocarps 

 have been taken at the end of July and the beginning af August. 



Geogr. Distrih. Known only from the Norwegian Polar Sea. Its most northerly 

 known locality is Maaso in Finmarken about Lat. N. 71°. 



Localities: The Norwegian Polar Sea: Nordlanden according to specimens in Kleen's 

 and Wahlenbeeg's herbaria, TromsO Amt near the town of Troraso; Finmarken at 

 MaasS, local, but abundant. 



Diploderma miniatum (Ag.) nob. 

 Ulva purpurea ft miniata Ag. Syn. Alg. p. 42. 

 Descr. Ulva miniata Lyngb. Hydr. Dan. p. 29. 

 Fig. » o » » I) t. 6, D. 



Porphyra miniata PI. Dan. t. 2394. 



» » KuTZ. Tab. Phyc. 19, t. 81. 



Diploderma miniatum Tab. nostra 18. fig. 9. 

 Syn. Porphyra miniata Kjellm. Spetsb. Thall. 1, p. 32. 

 » vulgaris Croall, PI. Disc. p. 461 (?). 



» » Dickie, Alg. Sutherl. 1, p. 144(?). 



Remark on this species. In the herbarium of the Copenhague Museum there are to 

 be found under the name of Porphyra (Ulva) miniata a considerable number of speci- 

 mens of the plant in question at different stages of development. The description 

 given by Lyngbye 1. c. of the alga named by him Ulva miniata accords well with 

 them. Thus I think we may safely assume that Lyngbye's description, as well as 

 C. A. Agakdh's description of Ulva purpurea /? miniata, is founded on some of these 

 specimens. The last author states expressly that the plant designed by him was from 

 Greenland, communicated by Wokmskiold; cp. Spec. Alg. 1, p. 407. However, this 

 Greenland species is no Porphyra, but a species of Diploderma, most closely allied to 

 the preceding one, though certainly specifically distinct from it. It has a different 

 colour, more firmness, at least when older, and almost no folds. Besides, it is always 

 dioecious, as far as my observations go. 



Habitat. At Spitzbergen I have found the present species in the lower part of 

 the sublitoral zone at a depth of 10 — 15 fathoms, attached to stones. I cannot state 

 anything with certainty with respect to its occurrence at Greenland. On the labels 

 appended to the specimens in the herbarium of the Copenhague Museum, we read: 

 »in mari ad saxa, ad stipites L. saccharinas (caule fistuloso) ad stipites L. saccharin sew; 

 from which it may be concluded that the plant is even here sublitoral, growing chiefly 



