Contribution. I. 91 



This species occurs in rock-pools between tides, or in the 

 upper part of the sublitoral zone, on a depth of 2 — 5 fathoms. 

 It is most often to be met with on open coasts, and here it 

 attains a length of 30 cm., usually 10—15 cm. It bears 

 zoosporangia in the later part of June and, more richly, in 

 July. 



Distribution: Scattered along the whole coast, at some 

 places (Berlevaag, Mehavn) common but not plentiful. 



Gen. Leathesia (Gray.) J. G. Ag. 

 Alg. Syst. 2, p. 40; Gray. Brit. PL 1, p. 301; char. mut. 



Leathesia difformis (L.) Aresch. 

 Phyc. Scand. p. 376; Tremella difformis L. Fl. Suec. p. 429. 

 Descr. Leathesia marina J. G. Ag. Spec. Alg. 1, p. 52. 

 Fig, „ tubeviformis Harv. Phyc. Brit. t. 324. 



Corynephora baltica Kiitz. Tab. Phyc. 8, t. 2. 

 „ marina Kiitz. 1. c. t. 3. 



Exsice. Leathesia difformis Aresch. Alg Scand. exsicc. No. 101 et 214. 

 „ „ Hauck et Richt. Phyc. univ. No. 172. 



Syn. Chsetophora marina Lyngb. Hydr. Dan. p. 193. 



A litoral alga, growing in rock-pools in the upper part 

 of the zone, fastened to Cladophora gracilis. I have only 

 seen a few dwarfish specimens. 



Distribution: Only found at Berlevaag, very rare. 



Fam Myrionemacese (Thur.) 



in Le Jol. Liste Alg. Cherb. p. 15; lim. mut. 



Gen. Myrionema Grev. 

 Crypt. Fl. No. 300, sec. J. G. Ag. Spec. Alg. 1, p. 47. 



Myrionema strangulans Grev. 

 1. e. 

 Qmr. Myrionema strangulans Harv. Phyc. Brit, t, 28Q, 



