TO THE EMBRYOLOGY OF AMPHIBIA. 



39 



third egg, the embryonic axis was exactly at right angles to the 

 same plane. 



In the fourth group, only three eggs out of five were good. 

 In one of these, the embryonic axis nearly coincided with the 

 first cleavage ; in the second, it was inclined about 60°, and in 

 the third, 40° to the first cleavage plane. 



When tabulated, the results may be expressed as follows : — 



When the two Bufo eggs in which the embryonic axis was 

 at right angles to the first cleavage plane are added to the list, 

 the total of such es^s becomes 6 out of 12. I admit that the 

 number is altogether too small to allow us to draw any general 

 conclusion, but the fact remains that the percentage of am- 

 phibian eggs in which there is a definite relation between the 

 embryonic axis and the earlier cleavage planes is quite large, and 

 that in such cases, the first named axis coincides with the second 



