viii CONTENTS. 



CHAP 



PAGE 



X. Heredity (continued)— The Principle of Structural Mean— Pre- 

 potency — Physiological and Pathological Blendings . . 74 



XI. Heredity (continued) — The Fixity of Structural Characters in 

 Inverse Proportion to their Age, Ancestral or Individual — 

 All Diseases' of Recent Ancestral Date — The Vis Medicatrix 

 Naturce — The Tendency of Recently Acquired Characters to 

 Disappear under Ancestral Forms of Environment ... 84 



XII. Heredity (continued) — Reversion—Its Two Chief Causes — Pecu- 

 liarity in the Evolutionary Process and Partial Dissolution of 

 a Mature Tissue . . . 104 



XIII. Heredity (continued)— A Consideration of the Different Modes by 

 which Organic Potentialities may become Actualities — Some 

 further Bearings of the Principle of Reversion upon Pathology 

 — Summary 115 



XIV. Heredity (continued) — Influence of the Male Element upon the 

 Female Organism — Inheritance of Acquired Structural Cha- 

 racters 123 



XV. The Causation of Structure {continued) — The Influence of Ante- 



partem Environment upon Structure 127 



XVI. The Influence of Environment upon Structure — The Influence of • 



the Ante-partem Environment (continued) — Differences in E 

 the Prime Cause of Natural Variations 138 



XVII. The Influence of Environment upon Structure (continued) — 

 The Influence of the Post-partem Environment, considered 

 from the Pathological Point of View 147 



XVIII. The Morbid Inter-action of Structure and Environment— All 

 Disease Processes probably attended by Structural Change, 

 and therefore Natural Variations — Structural Deficiency . 156 



XIX. The Symbolical Method of Expressing the Relative Share taken 



by Structure and Environment in Causation .... 163 



XX. Some Further Applications of the Symbolical Method . . .168 



XXI. Recapitulation j^. 



