THE PROBLEM OF SEX IN PLANTS 361 
of new characters there would be no opportunity for the 
improvement of plants either by nature or by man. 
The results of all studies and discussions of the question 
of sex lead us to recognize the fact that it is still largely an 
unsolved mystery. We must make further and more 
accurate observations, and be careful and logical in our 
reasoning, before we can hope to solve this difficult 
problem. 
