TABLE OF CONTENTS 



CHAPTER I. EVOLUTION DEFINED. 



Organic evolution and bionomics, 1; Meaning of evolution, 2; 

 Encasement theory, 2; Theory of epigenesis, 3; Evolution of the 

 species or transmutation, 3; Cosmic evolution, 4; Spencer's form- 

 ula of evolution, 5; Biologic evolution and cosmic evolution not 

 the same, 6; Usefulness of the term bionomics, 7; The flux of na- 

 ture, 7; Comprehensiveness of the science of organic evolution, 8; 

 The immanence and permanence of law, 9; Evolution not neces- 

 sarily progress, 10; Theory of descent, 10. 



CHAPTER II. VARIETY AND UNITY IN LIFE. 



Range of variety, 12; Meaning of species, 13; Number of species, 

 14; Extinct species, 16; Changes of species with time and place, 

 18; Variety in life a factor in the history of the globe, 21; Unity 

 in life, 22. 



CHAPTER III. LIFE, ITS PHYSICAL BASIS AND SIMPLEST EXPRES- 

 SION. 



Live things and lifeless things, 25; The basic distinction between 

 life and non-life, 26; Protoplasm, 26; Chemical make-up of proto- 

 plasm, 27; Physical make-up of protoplasm, 28; The cell, 30; The 

 simplest animals, 32; Differentiation and animal types, 32; The 

 genealogical tree, 36; Primary conditions of life, 38; Origin of life, 

 41: Spontaneous generation, 42; Where did life begin on the 

 earth, 47. 



CHAPTER IV. FACTORS AND MECHANISM OF EVOLUTION. 



The fact of descent, 48; Darwinism not synonymous with de- 

 scent, 49; Factors in descent, 49; Variation, 50; Selection, 51; 

 Prodigality of production, 52; Heredity, 53; Isolation, 53; Muta- 

 tion, 54; Orthogenesis, 55; Lamarckism and inheritance of ac- 

 quired chaiacters, 55; Adaptation, 56. 



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