BOTANY 



and crops, the origin and action of vitamines and 

 auximones and their relation to the plant organism, 

 the symbiotic relation between fungal hyphae and 

 the roots or other organs of plants in such families 

 as the heaths and the orchids. It is well to re- 

 member also that in the intensive study of any 

 crop and its improvement, the problem ultimately 

 becomes one in the broad aspects of its physiology, 

 and its environmental and genetic relationships. 



GENETICS 



Coming now to the subject of genetics, prob- 

 ably all will agree that this represents the field 

 of the most intense activity in the whole realm of 

 biology during the last twenty years. As a move- 

 ment it dates from 1900, when Mendel's principles 

 of heredity were simultaneously rediscovered by 

 de Vries in Holland, Correns in Germany, and 

 Tschermak in Austria. 



The story of Mendel and his experiments with 

 garden peas in the cloister garden at Brtinn, in 

 Moravia, is now almost a household tale ; how by 

 experimenting on the inheritance of single charac- 

 ters at a time, such as yellow or green, round or 

 wrinkled peas, he discovered the fundamental 

 principle that the differences were independently 

 inherited, the determiners for each pair of charac- 

 ters segregating independently in the germ-cells ; 

 and how his discovery, having been made before 



