CONTENTS xix 



CHAPTEK XXV 



PAQE 



1894. Pfeiffer's experiments — The Buda-Pest Congress — 

 Extracellular destruction of microbes — Reaction of the 

 organism against toxins — Dr. Besredka's researches — 

 Macrophages — The Moscow Congress — Bordet's experiments 158 



CHAPTEE XXVI 

 1900. Immunity — Natural immunity — Artificial immunity . 168 



CHAPTEK XXVII 



1893-1905. Private sorrows— Death of Pasteur — Ill-health 

 — Senile atrophies — Premature death — Orthobiosis — 

 SyphiUs (1905) — Acquisition of anthropoid apes (1903) . 181 



CHAPTER XXVIII 



Researches on the intestinal flora — Sour milk . . .196 



CHAPTER XXIX 



1908. The Nobel Prize — Journey to Sweden and Russia — A 



day with Ldon Tolstoi . . . . .199 



CHAPTER XXX 



Intestinal flora — Infantile cholera — Typhoid fever — Articles on 



popular Science ..... 206 



CHAPTER XXXI 



1911. Expedition to the Kalmuk steppes to study tuberculosis — 



Plague ....... 210 



CHAPTER XXXII 



Further researches on the intestinal flora — Forty Yearif Starch 



for a Rational Conception of Life . . .220 



