ANATOMY AND DEVELOPMENT. 



213 



The following table will help to make this matter 

 clearer. 



Of course the above table has no concern with the 

 actual time (hours and days) from the commencement 

 of the development at which such and such an event 

 occurs. The type of Ascidian referred to in the above 

 description is a simple Ascidian like Ciona or Phallusia. 



The above table also shows how the development of 

 the Ascidian and of Amphioxus moves along parallel 

 lines up to a certain point, and then at the time of the 

 outgrowth of the tail in the embryo of the former and the 

 hatching of the embryo of the latter, divergences set in. 



