240 



J. GRAY 



replaced in normal sea-water, it very rapidly returns to the 

 stage of cleavage which it had reached prior to being placed in 



Text-fig. 5, 



I IT 



Normal sea-water. Acid sea-water. 



Ill 



Normal sea-water. 



d 



Effect of acid sea-water on the form of a dividing egg. 



acid sea-water : it then proceeds to complete the division at 

 the normal — relatively slow — rate. The distinction between 

 the two phases of recovery from the acid is most marked. 



