42 THE AMPHIOXUS. 



I did not here, it is true, follow the processes of 

 fertilization with reference to the alterations of the 

 nucleus with any greater accuracy, as I had already 

 done this before sufficiently with thoroughly favour- 

 able objects. Yet I was able to point out observations 

 in accordance with the now generally received views. 

 Among the changes of the germinal vesicle, by which 

 the latter is withdrawn from observation, is to be 

 placed the ejection of the polar body ; and next to 

 this follows the fertilization. After the fertilization, 

 and before the beginning of the segmentation a 

 nucleus was again to be noticed in the egg. 



