THE DESCENT OB OBIGIN OF MAN 45 



that the embryos of wonderfully differ ent forms should still 

 retain, more or less perfectly, the structure of their common 

 progenitor. No other explanation has ever been given of 

 the marvellous fact that the embryos of a man, dog, seal, 

 bat, reptile, etc., can at first hardly be distinguished from 

 each other. In order to understand the existence of rudi- 

 mentary organs, we have only to suppose that a former 

 progenitor possessed the parts in question in a perfect state, 

 and that under changed habits of life they became greatly 

 reduced, either from simple disuse or through the natural 

 selection of those individuals which were least encumbered 

 with a superfluous part, aided by the other means previously 

 indicated. 



Thus we can understand how it has come to pass that 

 man and all other vertebrate animals have been constructed 

 on the same general model, why they pass through the same 

 early stages of development, and why they retain certain 

 rudiments in common. Consequently we ought frankly to 

 admit their community of descent; to take any other view, 

 is to admit that our own structure, and that of all the ani- 

 mals around us, is a mere snare laid to entrap our judg- 

 ment. This conclusion is greatly strengthened if we look 

 to the members of the whole animal series, and consider the 

 evidence derived from their affinities or classification, their 

 geographical distribution and geological succession. It is 

 only our natural prejudice, and that arrogance which made 

 our forefathers declare that they were descended from demi- 

 gods, which leads us to demur to this conclusion. But the 

 time will before long come, when it will be thought wonder- 

 ful that naturalists, who were well acquainted with the com- 

 parative structure and development of man and other mam- 

 mals, should have believed that each was the work of a 

 separate act of creation. 



