390 HEREDITY AND ENVIRONMENT 



amidst the multitude of fluctuations indicates 

 the wonderful stability of racial types and 

 teaches respect for Weismann's doctrine of a 

 germ plasm relatively stable, independent and 

 continuous. 



Fig. 94. ' Common Colorado Potato Beetle, Leftinotarsa. 

 a, normal undecemlineata, b, the mutant augusto-vittata, c, the 

 mutant melanothorax, A, normal decemlineata, e, the mutant 

 tortuosa, t, the mutant defecto-punctata. (From Plate after 

 Tower.) 



