352 



Subject Index 



Valine, 201 



Variants, resistant, indirect selec- 

 tion of, 50 

 resistant, origin of, 48-50 

 Variation between sister cells, 64-77 



X-rays, effect of, on DNA, 309 



Yeast, cofactors of enzymic adapta- 

 tion in, 210-232 



Yeast, 



cytochrome oxidase synthesis in, 

 210-232 



directed hereditary changes of 

 fermentative properties of, 102- 

 140 



induced mutational changes in, 

 102-140 



inheritance of fermentative pro- 

 perties developed as result of 

 directed changes, 120-128 



Printed by Spottiswoode, Ballantyne & Co. Ltd., London and Colchester 



