652 Bashford Dean Memorial Volume 



that recapitulation is not to be given the scant courtesy with which it has come to be treated 

 by a modern school of embryologists. In a word, the present theme may be found to provide 

 a new (and critical) means of testing the value of the biogenetic law. 



These hopes and expectations led to the publication, in 1901, of Dean's article 

 entitled "Reminiscence of Holoblastic Cleavage in the Egg of the Shark, Heterodontus 

 (Cestracion) japonicus Macleay." This contribution is reviewed, in considerable detail, 

 later in the present paper. Our knowledge of the embryology of Heterodontus is still 

 incomplete, so that the possibilities suggested by Dean have never been fully explored. 



To Dr. E. W. Gudger, editor of the Dean Memorial Volume, I am indebted for many 

 helpful suggestions throughout the preparation of this article, and especially for taking 

 the major part in the difHcult task of making up the plates. 



MATERIAL AND RECORDS 



For the proper evaluation of any scientific record, it is necessary that the reader 

 should be informed concerning the identity, amount and source of the material, also the 



Text'figure 1. 



The Marine Zoological Station at Misaki, Japan. 



From a photograph by Bashford Dean, 1904, p. 198. 



