32 THE DESCENT OF MAX. Part I. 



a bat, &c., is utterly inexplicable. It is no scientific 

 explanation to assert that they have all been formed on 

 the same ideal plan. With respect to development, 

 we can clearly understand, on the principle of varia- 

 tions supervening at a rather late embryonic period, 

 and being inherited at a corresponding period, how it is 

 that the embryos of wonderfully different 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 embryo of a 

 man, dog, seal, bat, reptile, &c, can at first hardly be 

 distinguished from each other. In order to understand 

 the existence of rudimentary 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 super- 

 fluous part, aided by the other means previously indi- 

 cated. 



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 struc- 

 ture and that of all the animals around us, is a mere 

 snare laid to entrap our judgment. This conclusion 

 is greatly strengthened, if we look to the members of 

 the whole animal series, and consider the evidence de- 

 rived from their affinities or classification, their geo- 

 graphical 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 



