COSMIC PHILOSOPHY 



Even such a slight change as an increased thick- 

 ness of the woolly coat of a mammal may, by 

 altering the excretory power of the skin, affect 

 the functions of the lungs, liver, and kidneys, 

 and thus indirectly increase or diminish the size 

 of the animal, which in turn will modify its 

 speed, its muscular development, its mental fac- 

 ulties, and its habits of life. 



Having thus briefly indicated the capacity of 

 the theory of natural selection for explaining the 

 most general phenomena of organic variation, 

 let us in conclusion observe how admirably it 

 explains certain special phenomena, which do 

 not otherwise admit of scientific explanation. 

 For evidence of the signal success with which 

 Mr. Darwin has explained such otherwise un- 

 accountable facts as the dimorphism of cer- 

 tain flowers, the existence of neuters or sterile 

 females among bees and ants, the odoriferous 

 glands in mammals, the calcareous shells of 

 mollusks, the heavy carapace of the tortoise, the 

 humps of the camel, the amazingly complicated 

 contrivances through which orchidaceous plants 

 are fertilized by insects, the slave-making in- 

 stinct of certain ants, the horns of male rumi- 

 nants, and countless other phenomena, — for 

 all this, I must refer to Mr. Darwin's various 

 works. From the mass of phenomena to which 

 the theory of natural selection has been satisfac- 

 torily applied, I will only select as an illustra- 

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