FLOATING PLANTS 



123 



FIG. 40. HALOSPHJERA. (FROM MURRAY'S " INTRODUCTION TO 

 THE STUDY OF SEAWEEDS," BY PERMISSION OF MESSRS. 

 MACMILLAN.) 



In the sphere on the left the protoplasm has gathered round the 

 nuclei lining the wall ; that on the right has shed the outer 

 membrane, and the daughter cells have separated from the 

 wall ; below are four stages in the development of the zoospores. 



FIG. 41. 

 PERIDINIUM. (AFTER CLEVE.) 



FIG. 42. 

 TRICHODESMIUM ("BLAKE"). 



