PAGE 



XXll CONTENTS 



CHAPTER XII 



Doubtful Phenomena of Heredity — 



1. * Xenia ' and telegony ....... 383 



2. The influence of temporary abnormal conditions of the 



parents on the offspring ...... 386 



3. The transmission of diseases ..... 387 



PART IV. — THE TRANSFORMATION OF SPE- 

 CIES: ITS ORIGIN IN THE IDIOPLASM 



* CHAPTER XIII 



The Supposed Transmission of Acquired Characters — 



1. Difficulties in the way of a theoretical basis for this 



assumption ........ 392 



2. The hypothesis tested by facts ..... 396 



3. Climatic variation in butterflies ..... 399 



CHAPTER XIV 



Variation — 



1. Normal individual variation . . . . . .410 



2. Pathological variation ....... 428 



3. Summary of the above two sections and conclusions . 431 



4. Variations on a larger scale ...... 435 



a. The origin of these variations .... 435 



b. The transmission of these variations . . . 444 



SUMMARY AND CONCLUSION 450 



