Modijication of Germinal Coiislitution of OrgaiiisDis 



Mutants ^"•" Mutant. 

 , tgrm ^ 



/ 



\l^ 



Stem Mutants Stem Muta 



^P _ 7" , lopn 







O S 2 





o.sS-S 



Mutation Behavior as Observed by DeVries in O. Mutation Behavior as Produced in Leptmotarsa and 



Lamarckianaand HisHvoolheaisof JVlutat.on Periods Cenetico-Djnamic Hypothesis o( Mutation and Pro- 



duction ot Mutating Stem Forms 



Fig. 70. — Diagram to show the differences between De\'ries' theory of the 

 origin of mutations, and the hyfxjthesis of Mutation as a result of hybrid 

 synthesis of the mutating stem form. 



