CONTENTS. 



PAGE 



The Unrolling of the Universe. Organic Evolution : The 



Development of Forms of Life, - 1 



Evolution as a Working Hypothesis, 4 



What Evolution Is Not, 6 



Variety in Life, 9 



Unity in Life, - 11 

 Heredity: The Great Conservative Force in Evolution, 13 



Theories of Heredity, - 15 



The Cell and Heredity, - - 16 



Amphimixis, - 19 



The Meaning of Sex, - 21 



The Cell Theory, 23 



The Physical Basis of Heredity, - - 26 



The Inheritance of Acquired Characters, - 28 

 The Inheritance of Acquired Characters Continued, - 31 



Significance of Morphology, - 34 



Ontogeny and Phylogeny, - 36 



Contemporary Evolution of Man, - 37 



The Gastrsea Theory of Hseckel, - - 40 



The Origin of the Eye, 43 



The Origin of the Ear, - 45 



The Law of Individuality, 47 



The Struggle for Existence, ' - 48 



Response to External Stimulus, 50 



Natural Selection, - 52 



