CONTENTS 



PAGE 



PREFACE T 



SYNOPSIS ix 



INTRODUCTION . 1 



CHAP. 



I. THE SCOPE OF THE ENQUIRY ... 3 



II. CONDITIONS MODIFYING THE CHARACTERS 



OP BACTERIA 13 



III. A CONSIDERATION OP THE EVIDENCE . 28 



IV. VARIATIONS IN MORPHOLOGY ... 37 



V. VARIATIONS IN FERMENTING POWER . 50 



VI. VARIATIONS IN VIRULENCE . . .71 



VII. VARIATIONS IN PATHOGENICITY . 94 



VIIL THE POSSIBLE OCCURRENCE OF TRANS- 

 MUTATION IN THE LIVING BODY . . 107 



IX. SUPPOSED INSTANCES OF TRANSMUTATION 

 BROUGHT ABOUT EXPERIMENTALLY . .116 



X. SUMMARY 140 



XI. THE ENZYME THEORY OF DISEASE . . 153 



XII. CONCLUSIONS 170 



APPENDIX. REFERENCES 171 



a 



