EVOLUTION. 19 



grees. Analogy teaches that this hae: always been 

 the order of nature. By these evidences fron 

 fossils, Huxley declares : " The evolution of many 

 existing forms of animal life from their predecessors 

 is no longer an hypothesis, but an historical fact." 



The horse has changed the structure of his feet to 

 conform to altered circumstances that make it desira- 

 ble for him to possess speed. By natural selection 

 and the survival of the swiftest, the variations toward 

 the present hoof have been preserved. Some may 

 wonder that such degcneraiion of parts is called evo- 

 lution, but the changes that occur are for the advan- 

 tage of the animal, and therefore are truly an advance. 



All the organs of the body are traced upward in 

 gradual stages from the simplest beginnings. A 

 favorite appeal for the special -creation theory is to 

 point to the marvellous structure of the human eye. 

 But the eye, brain, heart, lungs, limbs, and digestive 

 organs are found in different animals in conditions that 

 show a gradual ascent in structure, from the merest 

 suggestion of the organ to its most perfect form. 

 From the air-bladder of the fish to the lungs of man 

 we have an ascending series of forms, and in the 

 mud-fish, that spends half the year in dry mud and 

 half the year in water, we find the transition from 

 the bladder to the lung, — another " missing link." 

 Scales and feathers are developments of the skin, 

 and in the penguin can be seen the intermediate 

 forms, half scale and half feather. 



