CONTENTS. 



Page. 



Pbeface III-V 



THE PROBLEMS AND MATERIALS. 

 Chapteb L The Pboblems and Concepts of Evolution. 



Introduction 1 



Physical Conception of Life 1 



Nature of the Individual 3 



Basis of Characters in Non-Living and Living Substances 5 



Relation of External and Internal Factors 5 



Categories of Organic Characteristics 6 



Evolution and Transmutation 8 



Hypotheses of Species Transmutation 11 



Processes of Evolution 18 



Factorial Theory of Evolution 21 



Chapteb II. The Matebials, Theie Taxonomy and Natubal Histoby. 



Introduction 24 



Methods of Obtaining Materials 24 



Character and Source of Materials 25 



Species and Subdivisions of the Lineata Group 31 



Description of the Species 32 



Evolution and Phylogeny of the Lineata Group 69 



Chapteb III. The Pboblems of Gametic Constitution. 



Introduction 72 



The Germ-plasm Concept 76 



The Gametic Agents 78 



Metathesis of Gametic Agents 80 



Architecture of the Germinal Material 83 



Chapteb IV. Reactions and Peoducts in Intebspecific Cbosses. 



Methods of Culture ^^ 



Leptinotarsa signaticollis X L. diversa ^^ 



Leptinotarsa undecimlineata X L. signaticollis 124 



Leptinotarsa undecimlineata X L. diversa 142 



Discussion of the Results Derived in Crossing the Species L. diversa, L. sig- 

 naticollis, and L. undecimlineata 143 



Chapteb V. Reactions and Pboducts in Intebspecific Cbosses. 



Leptinotarsa diversa X L. decemlineata 146 



Leptinotarsa decemlineata X L. oblongata 152 



Leptinotarsa decemlineata X L. viultitwniata 163 



Leptinotarsa multitceniata X L. oblongata 168 



Summary and Discussion of the Crossing of Species 169 



Chapteb VI. The Pboblems of Hetebogeneity. 



Introduction 184 



Problems of Heterogeneity 185 



Causes of Heterogeneity 190 



Analysis of Heterogeneity 191 



VII 



