134 NATURAL SCIENCE. August, 1894. 



actual occurrences ol embryology and their theoretical significance. 

 Since he takes a more epigenetic view, he proposes to attempt to 

 formulate his ideas. This he will do first in a criticism of Weis- 

 mann's theory of preformation, and then in an exposition of his own 

 epigenetic theory. An account of these two sections will appear in 

 succeeding numbers of Natural Science. 



P. Chalmers Mitchell. 



