THE BIOLOGY OF THE CELL SURFACE 



(nucleus In the resting stage) is also swollen. The ecto- 

 plasm is so narrowed that its fibrillae seem absent; in other 





o 





o 



Fig. 2ob. — Section of egg, in the same stage as that of Fig. zoa, after having 

 been returned to sea-water. The yolk spheres are regaining normal structure; 

 water in drops moves toward the periphery. 



Fig. 20C. — Same history as that of Fig. 20b, but a later stage of development. 



words, the pressure of the egg-contents has reduced the 

 width of the ectoplasm. On return to normal sea-water, 

 the egg shrinks and the water-drops then appear. The 



7J2 



