THE ALG^E 



133 



While most of the Fucaceae are attached, Sargassum, Cysto- 

 phylluin, and some others are found floating and vegetating freely 

 far from any land. It is still uncertain whether or not some of 



FIG. 104. A-E, Fums furcatus. A, oogonium (X 150). B, C, egg-cells escaping 

 from the oogoninm. D, filaments, with antheridia. E, antheridia, more highly 

 magnified. F, F. vesiculosus, oogonium discharging the egg-cells. G, fertilization 

 of the egg. H, spermatozoids more highly enlarged. I, young plant. J, conjuga- 

 tion of the sexual nuclei ; o, egg-nucleus ; sp, sperm-nucleus. K, young oogonium 

 of Ascophyllum nodosum, with dividing nucleus. (J, K, after FARMER.) 



these species may spend their whole life as free-swimming or pela- 

 gic forms. These floating masses of seaweed serve as shelter for 

 a great variety of marine animals, small fish even being found living 

 in them. 



