no THE DOCTRINE OF DESCENT. 



the caterpillar and butterfly serve as an example. " Im- 

 perfect and evanescent a creature though the butterfly 

 may be as to its species, when compared to the mammal, 

 m the metamorphosis which it accomplishes before our 

 eyes, it nevertheless exhibits the superiority of a more 

 perfect over a less perfect animal. This consists in the 

 decisiveness of its parts, the security that none can be 

 put or taken for the other; that each is destined for its 

 function, and remains constant to it for. ever." Now, 

 however, in the most perfect creatures, the Vertebrata, 

 there appeared before Goethe's eye, a similar rudimentary 

 organ, metamorphosing itself within the individual; this 

 was the vertebra. He followed it in its transformations 

 along the vertebral column. Impossible as it may be, 

 by placing together the first vertebra of the neck with 

 the last tail bone to infer their identity, it becomes mani- 

 fest in the gradual transition. 



But what lies in front of the first vertebra of the 

 neck? Is the cranium something absolutely different, 

 something new, not identical with the vertebral column? 

 This was another perturbing thought which pursued 

 Goethe's every footstep. He pondered and compared; 

 it could not be otherwise; the cranium must belong to 

 the vertebral column, must be nothing more than a part 

 of the vertebral column. Through the vacillations of 

 his conceptions, he was, as he later expresses himself on 

 another occasion, " as an honest observer transported into 

 a sort of frenzy." Then, when in 1790 he picked 

 up a bleached sheep's skull in the Jewish cemetery at 

 Venice, "' the derivation of the cranium from the verte- 

 bral bones was revealed to him." The more special 

 history of Comparative Anatomy has shown how ex- 



