CONTENTS. 



Page. 



FBEFAOE III-V 



THE PROBLEMS AND MATERIALS. 



Chaptbb I. The Fbobij:ms 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 6 



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, Their Taxonomy and Natubal Histobt. 



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 



Chaptbb III. The Pbobijims 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 Pboduots in Intebspecifio Cbosses. 



Methods of Culture 90 



Leptinotarsa signaticollis X L. diversa 94 



Leptinotarsa undecimlineata X L. signaticollis 124 



Leptinotarsa iindecimlineata X L. diversa 142 



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

 naticollis, and L. wndecimlineata 143 



Chaptbb V. Reactions and Pboducts in Interspecific Cbosses. 



Leptinotarsa diversa X L. decemlineata 146 



Leptinotarsa decemlineata X L. oblongata 152 



Leptinotarsa decemlineata X L. multitwniata 163 



Leptinotarsa multitwniata X L. oblongata 168 



Summary and Discussion of the Crossing of Species 169 



Chapteb VI. The Pboblems op Hetebogeneity. 



Introduction 184 



Problems of Heterogeneity 185 



Causes of Heterogeneity 190 



Analysis of Heterogeneity • 191 



VII 



