o42 KJELLMAX, THE ALG.E OF THE AliCTIC SEA. 



Litlioderma lignicola. Fig. 8—11. 



Fig. 8. Piece of wood covered with the plant. Vi- 



» 9. Part of tlie basal layer of the froud. *"%. 



» 10. Radical transverse section of the frond. **%. 



» 11. Horizontal tangential section of the frond, ^""/i- 



Dictyosiphon corymbosus f. abbreviata. Fig. 12—Ii>. 



Fiij. 12. Older specimen bearing zoosporangia. '/i- 



» 13. Part of transverse section of the lower part of the main axis of the froud. -"*; 



» 14. Part of branch, bearing zoosporangia, seen superficially. 



» 15. Part of transverse section of the same. -""/i. 



100/ 

 ;1- 



Chorda fllum. f. crassipes. Fig. 16. 



Fig. 16. Full-grown specimen. Vi- 



Phloeospora pumila. Fig. 17. 



Fig. 17. Lower part of the frond with rhizines. '%. 



PLATE 27. 

 Pylaiella varia. Fig. 1 — 13. 



Fig. 1. Part of sterile individual. *'*/j. 

 » 2. Zoosporangia developed in different manners. ^"Vi- 



Pylaiella nana. Fii/. 13 — 15. 



Fig. 13. ^'egetative part of the frond. ""',]. 

 1) 14. Part of vertical ceD-row bearing two gametangia (zoosporangia multilocularia) one, of which is void. "Vi- 

 » 15. Parts of vertical cell-rows bearing zoosporangia (?). "-^'j. 



PLATE 28. 



Monostroma saccodeum. Fig. 1—10. 



Fig. 1 — 2. Young individuals, still cystiform. Vi- 

 » 3 — 4. Older, full-grown individuals of somewhat different habit, '/'i- 

 » 5, Lowest part of the frond, seen superficially. *'%■ 

 » 6. Transverse section of the same part. '"'%■ 



7. Part of the vegetative portion of the frond. *'"'/i. 

 » 8. Transverse section of the same. *''*'/i. 

 » 9. Part of the zoosporiferous portion of the frond. *'"'/j. 

 » 10. Transverse section of the same. '""/i. 



