I6 AN INTRODUCTION TO MODERN GENETICS 



CHAPTER PAGE 



D. GENE MUTATION 



1. Spontaneous mutation 380 



2. The induction of mutation 382 



3. Mutations and X-rays 384 



4. Rates of single mutations 390 



E. THE CHROMOSOME AND THE GENE 



1 . The chemical nature of chromosomes 392 



2. The nature of the gene 397 



Appendix 



LABORATORY METHODS FOR CLASS-WORK ON 



DROSOPHILA 403 



BIBLIOGRAPHY AND AUTHOR-INDEX 409 



SUBJECT INDEX 435 



