230 THE STRUCTURE OF FLOWERS. 



CHAPTER XXV. 



SEXUALITY AUD THE ENVIRONMENT. 



General Observations. — As the environment is now known 

 to have most potent influences on the anatomical structure 

 of the .vegetative system of plants, thereby affecting their 

 outward and visible morphological characters as well ; so are 

 there many causes which affect the reproductive system, at 

 one time influencing the androecium, at another the gjncB- 

 cium, favouring them or the reverse as the case may be ; so 

 that either sex or even both may be entirely suppressed, and 

 a hermaphrodite flower become male, female, or neuter. 



With regard to the most general agency, there seems to 

 be a tolerably uniform consensus of opinion that the female 

 sex in plants is correlated with a relatively stronger vital 

 vigour than the male ; and this is just what an d priori 

 assumption would look for, as the duration of existence and 

 the work to be done in making fruit require a greater 

 expenditure of energy than the temporary function of the 

 stamens. 



We must, however, distinguish between a healthy vital 

 vigour, and any excessive vegetative growth, as occurs under 

 high cultivation, and as is often the result of intercrossing. 

 If this latter surpass the requisite or optimum conditions for 

 the healthy performance of the functions of all the organs 



