334 KJELLMAN, THE ALGtE OF THE AKCTIC SEA. 



Fig. 3. Part of an older specimen in transverse section. Vi- 



» å. Branch with conceptacles of sporangia, seen from above. '/i- 



« 5. Part of tliin transverse section of a branch. *%. 



" 6. Part of median thin section of a branch. *%. 



" 7. Part of oue of the outer concentric layers of a thin transverse section. '*"%. 



» 8. Part of the central layer iu a thin transverse section. *'"'/i. 



" 9. Part of layer of tissue in a thin median section. *"%. 



» 10. Part of superticial, tangential thin section. '"'%. 



» 11. Part of the roof a conceptacle of sporangia, delivered from lime. '"'% . 

 " 12-— U. Sporangia. ^o^/i . 



PLATE 4. 

 Litliotliamnion intermedium. 



Fiij. 1. P'ull-grou'n speeimen. Vi- 



" 2. Half of an older specimen, seen from the cleaving-surface. Vi- 



» 3. Branch with conceptacles of sporangia. -/i- 



« 4. Part of thin transverse section of a branch. ^"/j. 



>' 5. Part of thin median section of a branch. ^^/j. 



» 6. Part of one of the outer concentric layers of a thin transverse section. ^""/i- 



» 7. Part of the central layer of a thin transverse section. *'"'/i- 



» H. Part of layer of tissue in a thin median section. ''""/p 



u 3. Part of superticial, tangential thin section. 

 » 10. Sporangium. *'"'/i- 



400/ 



1- 



PLATE 5. 

 Lithothamnion alcicorne. VUj. 1—8. 



Fiij. 1. Older, fuUy developed specimen. */j. 



» 2. Branch with conceptacles of sporocarps and of sporangia. Vi- 



" 3. Part of thin median section of a branch. '"'/j. 



» å. Part of thin transverse section of a branch. *%. 



» 5. Part of one of the outer concentric layers of a thin transverse section. ''""/j. 



" 6'. Part of central layer of thin transverse section. *'"'/]- 



» 7. Part of layer of tissue in a thin median section. *"%. 



)) 8. Sporangium. *"%■ 



Lithothamnion norvegicum. YUj. O— 10. 



Fig. D. Specimen from the north-wcst coast of Norway. Vi- 

 w 10. Specimen from the south-west coast of Norway. Vi* 



Lithotliamnion foeeundum. Fig. 11—19. 



Fig. 11. Part of specimen incrusting a stone. Vi- 

 » 12. Part of the crustaceous frond bearing conceptacles of sporangia, seen from above. Vi- 



