23 



landic plants must rather be regarded as thick plants. The 

 midrib is broad, 1— 1,2 cm. in the inferior portion of the lamina 

 measured in dry state, and its transverse section is narrowly 

 elliptical as in other varieties of this species. The sporophylls 

 are distant below, less distant upwards as stated by J. Agardh. 

 In the superior sterile portion they reach their greatest breadth 

 (10 cm. dried, 15 cm. soaked) which by far exceeds the measure 

 stated by J. Agardh («sesquipoUicem»); but as the breadth of 

 the sporophylls is considerably variable in A. grandifolia (comp. 

 Kjellm. Spetsb. 11, p. 11), I do not think that any essential 

 importance may be attached to this difference. 



According to Rosenvinge (Grl. Havalg. I.e.) and according 

 to what I have seen myself, the position of the sporophylls is 

 not of any systematic importance ; the same may be said of 

 the consistence of the lamina, as it is dependant of age (Kjellm. 

 Spetsb. 1. c, Rosenv. Grl. Havalg. 1. c.) and locality (Rosenv. 1. ci. 

 Nor to the length of the stipe may any systematic importance 

 be attached, as it increases with the age of the plant. Thus 

 the above mentioned Greenlandic plants might possibly be re- 

 garded as an old A. Pylali v. typica; but on account of our 

 present knowledge of v. typica, it is not justifiable to determine 

 them as belonging to this variety. 1 have therefore chosen to 

 identify them with A. gratidifolia, as they agree with this species 

 better than any of all the described species of Alaria. 



Gathered with sporangia in June. The specimens were 

 growing in a luxuriant vegetation of Laminaria^ in a depth of 

 3 — 5 fathoms, in rapid current, on a steep rock-side, sheltered 

 by a sea cliff, where no drift ice normally would appear. 



a. typica. 



Gr. or.: Smalsund. 



ß. memhranacea. 



Gr. or.: Tasiusak, Tiningnekelak, Nualik, Kap Borlase Warren. 



y. grandifolia. 



Gr. or.: Ikerasak. 



