Oogonium Liberation and the Embryogony of Some Fucaceous Algae. 13 



ment the wall ruptures at one end by the pressure of the growing 

 rhizoids (Fig. 14, PL. II) and the sporeling becomes free 

 thereafter. 



During the study of the sporeling-development I often met 

 with different abnormities and some which are interesing are 

 shown in text-fig. 5. These abnormities are often found, especially 

 in *S. encrvc, and all these figures were sketched from the sporelings 

 of this alga. Fig. 5,« represents an abnormity in which the first 

 segmentation wall is oblique to the long axis, fig. 5, /> is the later 

 stage of this abnormity, c and d of the same figure show something 

 like ' Simultan-dreier' and 'Simultan- vierer.' Superfluous nuclei 

 in the oo;_onium often fail to degenerate, and this results in the 

 formation of a curious abnormity in the later development (Fig- 

 5/). 



In conclusion I wish to express my hearty thanks to Professor 

 K. Fujii for his v^'Juable suggestions and assistance given me 

 during the progress of this work and to Professor Iijima, the 

 director of the Misaki Marine Biological Station through whose 

 kindness many facilities were afforded me in the course of my 

 investigations. 



Botanical Institiitc, 



College of Science, 



Tokyo Imperial University. 



Publ. March. 31st, 1913. 



