226 MISCELLANEOUS OBJECTIONS. 



protest. It is notorious that the wings of birds and bats, 

 and the legs of horses or other quadrupeds, are undistin- 

 guishable at an early embryonic period, and that they be- 

 come differentiated by insensibly fine steps. Embryological 

 resemblances of all kinds can be accounted for, as we shall 

 hereafter see, by the progenitors of our existing species 

 having varied after early youth, and having transmitted 

 their newly acquired characters to their offspring, at a cor- 

 responding age. The embryo is thus left almost unaffected, 

 and serves as a record of the past condition of the species. 

 Hence it is that existing species during the early stages of 

 their development so often resemble ancient and extinct 

 forms belonging to the same class. On this view of the 

 meaning of embryological resemblances, and indeed on any 

 view, it is incredible that an animal should have undergone 

 such momentous and abrupt transformations as those above 

 indicated, and yet should not bear even a trace in its 

 embryonic condition of any sudden modification, every 

 detail in its structure being developed by insensibly fine 

 steps. 



He who believes that some ancient form was transformed 

 suddenly through an internal force or tendency into, for 

 instance, one furnished with wings, will be almost com- 

 pelled to assume, in opposition to all analogy, that many 

 individuals varied simultaneously. It cannot be denied 

 that such abrupt and great changes of structure are widely 

 different from those which most species apparently have 

 undergone. He will further be compelled to believe that 

 many structures beautifully adapted to all the other parts 

 of the same creature, and to the surrounding conditions, 

 have been suddenly produced ; and of such complex and 

 wonderful coadaptations, he will not be able to assign a 

 shadow of an explanation. He will be forced to admit that 

 these great and sudden transformations have left no trace 

 of their action on the embryo. To admit all tnis is, as it 

 seems to me, to enter into the realms of miracle, and to 

 leave those of science. 



