The Theory of Evolution Jj 



length and form of the beak, and in other characters, that 

 they would certainly have been ranked as distinct genera 

 if found in a state of nature. But when the nestling birds 

 of these several breeds were placed in a row, though most of 

 them could just be distinguished, the proportional differences 

 in the above specified points were incomparably less than in 

 the full-grown birds. Some characteristic points of differ- 

 ence — for instance, that of the width of the mouth — could 

 hardly be detected in the young. But there was one remark- 

 able exception to this rule, for the young of the short-faced 

 tumbler differed from the young of the wild-rock pigeon, 

 and of the other breeds in almost exactly the same propor- 

 tions as in the adult state.' " 



Hurst concludes that : " The more the adult structure 

 comes to be unlike the adult structure of the ancestors, the 

 more do the late stages of development undergo a modifica- 

 tion of the same kind. This is not mere dogma, but it is a 

 simple paraphrase of Von Baer's law. It is proved true not 

 only by the observations of Von Baer and of Darwin, already 

 referred to, but by the direct observation of every one who 

 takes the trouble to compare the embryos of any two verte- 

 brates, provided only he will be content to see what actually 

 lies before him and not the phantasms which the recapitu- 

 lation theory may have printed on his imagination." 



The growth of the antlers of stags is cited by Hurst in 

 order to illustrate that what has been interpreted as a re- 

 capitulation may have a different interpretation. " Each 

 stag develops a new pair of antlers in each successive year, 

 and each pair of antlers is larger than the pair produced in 

 the previous year. This yearly increase in the size of the 

 antlers has been put forward as an example of an ontogenetic 

 record of past evolution. I, however, deny that it is such a 

 record." 



" The series of ancestors may have possessed larger antlers 

 in each generation than in the generation before it. It is not 



