The Theory of Evolution 47 



be supposed to have taken place. Fleischmann points out 

 that these facts were supposed to be in full harmony with 

 the theory of descent. 



The analysis of the origin of the foot of the horse gave 

 even better evidence, it was claimed, in favor of the theory. 

 The foot consists of a single series of bones corresponding 

 to the middle finger and toe. When, as sometimes happens, 

 individual horses are found in which in addition to the single 

 middle finger two smaller lateral fingers with small hoofs 

 appear, the followers of the descent theory rejoiced to be able 

 to bring this forward as a confirmation of their doctrine. 

 The occurrence was explained as a sporadic return to an 

 ancestral form. The nai've exposition of the laws of in- 

 heritance that were supposed to control such phenomena 

 was accepted without question. And when finally a large 

 number of fossil remains were found by paleontologists, — 

 remains showing a gradual increase in the middle finger, 

 and a decrease in size of the lateral fingers, — it was sup- 

 posed that the proof was complete ; and anatomists even 

 went so far as to hold that the original ancestor of the 

 horse was a five-fingered animal. 



This same law of type of structure was found to extend to 

 the entire vertebrate series, and the only plausible explana- 

 tion appeared to be that adopted by Darwin and his fol- 

 lowers, namely, that the resemblance is the result of the 

 blood-relationship of the different forms. But a simple com- 

 parison of the skeleton of the limbs if carried out without 

 theoretical prejudice would show, Fleischmann thinks, that 

 there is only a common style, or plan of structure, for the 

 vertebrates. This anatomical result has about the same 

 value as the knowledge of the different styles of historical 

 architecture — that, for instance, all large churches of the 

 Gothic period have certain general principles in common. 

 The believers in the theory of descent have, however, he 

 thinks, gone beyond the facts, and have concluded that the 



