CONTENTS ix 



CHAPTER H. 



SUGGESTIONS FOE RELIABLE HYPOTHESES OF EVOLUTION. 



1. DIRECT OBSERVATION AND THE FACTS OF ANIMAL AND PLANT PAGE 



GEOGRAPHY 164 



2. SUGGESTIVE POINTS IN THE DOMAIN OF PARASITISM AND 



SYMBIOSIS . . .177 



ANT GUESTS AND TERMITE GUESTS: WASMANN (ADAPTIVE 



PHENOMENA IN SYMBIOTICS) . . . . . .188 



3. SUGGESTIVE POINTS IN THE EMBRYOGENY OF THE PRESENT 



ORGANISMS ........ 202 



4. SUMMARY OF THE COLLECTED RESULTS .... 228 



CONCLUSION ......... 230 



INDEX 



237 



