ANTICIPATION AND INTERPRETATION 33 



willing Nature had to slowly yield up her secrets, 

 and Evolution could not be conceived in its i^hy- 

 letic sense until all the knowledge embraced in 

 'filiation' or phylogeny had been more or less 

 fully attained. 



Let us first look at structure. Anatomy had 

 its infancy among the Greeks, and dissection was 

 rudely practised. Aristotle was descended from a 

 long race of physicians, yet his treatise on the 

 structure of man is believed to show that he did 

 not practise dissection. Scientific anatomy dates 

 back to Galen, while modern anatomy began with 

 the school of the University of Padua, where the 

 human body was first fully dissected. In struc- 

 ture Aristotle observed the law of analogy, as, 

 for example, in his comparison of the functions 

 of the fore and hind limbs. But the principle of 

 homology, or the fundamental likeness of type 

 structure between the fore and hind limbs, was 

 first pointed out by Vicq d'Azyr in 1805. Anal- 

 ogy is the will-o'-the-wisp of Evolution ; it is al- 

 ways leading us astray, as it did Geoffroy St. 

 Hilaire in the third period, for functionally simi- 

 lar forms and forms with an external resem- 

 blance are produced over and over again in Na- 

 ture, and do not always point to phyletic affin- 

 ity, while homolog}^ is one of our safest guides. 

 The relations of organs to each other, or the idea 

 that one structure is sacrificed for the develop- 



