CONTENTS 



PREFACE ''*°^ 



LIST OF ILLUSTRATIONS ...... lii 



PART I 

 THE NOTION OF SPECIES IS A CHEMICAL NOTION . . i 



The Living Substance of each Specific Form is a Mixture of a Number 

 of Chemical Entities — Each Specific Mixture differs from all others by 

 at least one Entity — Chemical Classification of Plants and Animals — 

 Groups and Series of Chemical Entities — Glycerides — Proteins — Natural 

 Mixtures — Bioproteins — Biotic and Abiotic Chemical Properties — 

 Heredity — Individual Variation — Mutation — Lamarckism 



PART II 



THE OBSERVABLE PROPERTIES OF EACH SPECIES ARE 

 PRODUCED BY REACTIONS OF ITS LIVING SUB- 

 STANCE 9 



Possible and Observable Properties — Range of Possibilities — Plasticity — 

 Variants — Complexity — Monotypic and Complex Species — Subspecies 

 — Pure Lines — Bud-Variation — Bud-Species — Continuous and Dis- 

 continuous Variation — Adaptation — Accommodation — Variation under 

 Cultivation — Latent Properties 



PART III 

 QUANTITATIVE METHOD AND PRIMORDIA . . . .25 



Summary of Parts I. and II. — Use of the Quantitative Method in the 

 Description and Classification of Species — Linnaeus — Latreille — Bertil- 

 lonage — Biometry — Quantitative Variation — Quetelet — Variation 

 Curves — Galton— Weldon — Pearson — Davenport — Biometrika — Appli- 

 cation of the Quantitative Method on the Study of Hybridization — 

 Mendel — The Mendelian Experiments in Relation to the Notion of 

 Species — Simple and Compound Properties — Primordia — Observable 

 Properties and Hereditary Factors — Segregation (Dissociation) of 

 Compound Properties into Primordia by Hybridization, Plasticity, 

 Gradation and in the Course of Individual Development — The Mendelian 

 Method of describing Hybrids is applicable on the Description of 

 Species — Phyllotaxis — Quantitative Investigation of Physiological 

 Functions 



