Fig. 119 Portion of fertile plant of Carpophyllum fiexuosum ( x i). 



whole megasporangium, not merely the inner wall and its contents, 

 is discharged and remains just outside the ostiole attached to the 

 conceptacle wall by a long mucilaginous stalk which is a secondary 

 development. In one subsection of the genus the ostiole of the 

 female conceptacle is closed by a disc-shaped gelatinous stopper, 

 which disappears when the oogonia are ripe. 



After fertihzation the first divisions take place whilst the zygote 

 is still attached to the parent plant by this long stalk. In 5. filipen- 

 dula fertile or degenerate reproductive organs are found in some of 

 the cryptostomata, and this fact has been taken to signify that these 

 sterile pits are abortive or juvenile conceptacles. The genus is 

 especially abundant in AustraUan waters, and one species, S. enerve^ 

 is employed in Japan as a decoration for New Year's Day because, 

 when dried, it turns green. Various species are also used in the 

 same country for food, but the chief claim to notoriety in this 

 genus is probably associated with 5. natans, the so-called Sargasso 

 weed, which from time immemorial has been found as large 

 floating masses in the Sargasso Sea near the West Indies, fre- 

 quent references to it being recorded in the stories of early travellers 



211 



