T8or THE RECAPITULATION THEORY. 369 



I do not deny that there may be exceptions to this last statement. 



I deny that any one of the theories as to the ancestry of the 

 vertebrates based exchisively on embryological grounds is worth the 

 paper it was written on. 



I maintain that much otherwise good embryological work has lost 

 much of its value through the bias produced in the minds of the 

 writers by the dominancy of the idea of recapitulation. 



Comparative anatomy gives some help : Palaeontology may give 

 even more : by their aid embryological facts may be explained : but 

 the facts of palaeontology can never be discovered by the study of 

 embryology. 



" Vestiges," and these only, can give any embryological clue to 

 past history which could not be equally well made out from com- 

 parative anatomy. In this last I may be wrong. 



I maintain that the applicability of von Baer's law to even a 

 single case would be a definite and final disproof of the Recapitulation 

 Theory even in its most reasonable forms. 



Finally, I assert that the applicability of von Baer's law in a large 

 number of cases is capable of being readily proved by anybody, by a 

 direct appeal to Nature, i.e., by the study of a few vertebrate embryos 

 taken at random. 



C. Hf.rbrrt Hurst. 



2B 



