36 



HEREDITY 



The struggle for existence is portrayed by the meadow mouse, sur- 

 struggie for rounded by its many enemies and yet continuing to main- 

 Existence tain an existence by virtue of its great birth-rate. 



The simpler features of the laws of Beredity as elucidated by Mendel 

 and bis followers are illustrated by the inheritance of 

 seed-coal color in the common pea, the color of sweet 



pens, and t lie coat-color of rats. 



R< turn l" the elevators and asa nd to the s< cond floor. 



Heredity 



ENLARGED MODEL OF A RADIOLARIAN 



