64 



Remark on the form of the species. Among the named spe- 

 cimens from Haugesund are some more densely branched, others 

 coarser and more sparsely branched, the former nearly according 

 with the most common form along the Norwegian coast, the above 

 f. norvegica, not unlikely being the typical form of the species, 

 and the latter partly agreeing with the form that I have called f. 

 australis partly forming intermediate forms. The form norvegica 

 is characterized by its much branched frond, frequently forming 

 subspherical masses about 3 cm. in diameter, the branches always 

 rather bent, more or less spreading, about 1— 1.3 mm. thick, sel- 

 dom a little anastomosing below and in general slightly attenuating 

 towards the tip, and the ends frequently rounded. The surface of 

 the frond is most commonly smooth, but now and then rather 

 uneven on account of local, scaly thickenings. PI. 16, fig. 1 — 11. 

 This form frequently grows gregarious in considerable abundance. 



The form saxatilis is nearly connected with the latter. It 

 appeal s always to grow more or less scattered, never in any great 

 number. It fastens itself to small stones, but in a more advanced 

 stage of development it occasionally detaches itself and lies free 

 on the bottom. It often rather resembles the preceding form in 

 habit, but it never attains the size of that form, being less bran- 

 ched, with shorter axes, but the branches nearly always more or 

 less bent, as in the named form. The branches often also are 

 coarser, up to about 1.8 mm. in thickness, not or slightly attenua- 

 ting upwards, with rounded or nearly obtuse ends. PI. 16, fig. 

 12 — 23. The surface is rather uneven, finely rugged, with more 

 or less numerous local and scaly thickenings. 



Another form also nearly connected with f. norvegica is the 

 form that I have named f. australis. It frequently is somewhat 

 coarser than f. norvegica, sparsely branched, the branches partly 

 short partly and more often rather long, 1.5—2 mm. thick, much 

 spreading, terete or somewhat compressed, cylindrical or slightly 

 attenuating towards the tip, with rounded ends, or now and then 

 with the tips rather compressed and the ends rounded or even, 

 nearly truncate. Some specimens that I received from Dr. Bornet 

 „drague a 1' embouchure de la reviere de Morlaix (Finistere)" belong 



