EVOLUTION. 41 



called a naturalist has accepted the theory of Evolu- 



A.' " 



tion. 



Summary. 



Now, to summarize the evidences previously 

 alluded to, we find : — 



1. The Nebular Hypothesis — the formation of 

 worlds from the moving •' star dust " — agrees with 

 all known facts concerning the solar system, and 

 is accepted as the best explanation of the universe. 



2. All the orders of the animal world show a con- 

 nection, more or less complete, by which an ascend- 

 ing tree of life spreads out from a common root. 



3. All the classes of the vegetable kingdom are 

 likewise allied by a continuous succession of forms. 



4. Animal and vegetable life meet in the lowest 

 forms and suggest a common origin. 



5. All vegetable and animal life originate in cells 

 of protoplasm which, to all appearance, are alike. 



6. Every animal before reaching its adult form 

 passes through forms common to the races below it. 

 These changes occur either wholly before birth, as in 

 the case of quadrupeds and man, or partly after birth, 

 as with frogs and butterflies. The only intelligible 

 way of accounting for this development of individuals 

 is to suppose that the races to which they belong 

 have developed in a similar manner from lower 

 orders, and the history of their descent is repeated in 

 the history of each individual. " Development re- 

 peats descent." 



