REPRODUCTION. 231 



veloping root. HANSTEIN (following upon the investigations of 

 HOFMEISTER) made a special study of embryonal development. 



The effects of fertilization are not limited to the gynoecium, 

 but are manifest in the entire flower. Death and loss of organs 

 which have served their function go hand in hand with new 

 processes of growth which now serve new purposes. The petals, 

 at times also the sepals, fall off; the stamens wither away. Fre- 

 quently the floral axis (receptacle, torus) takes part in the fruit- 

 formation, especially in epigynous flowers. Some of the physiologic- 

 al adaptations are as follows: structural arrangements to enable 

 the seed and fruit to withstand the period of vest, to distribute them 

 by wind and insects, and to insure a favorable course during ger- 

 mination. Some of these adaptations will again be referred to in 

 the following chapters. 



IY. THE MORPHOLOGY AND PHYSIOLOGY OF THE 

 SEED AND FRUIT OF PHANEROGAMS. 



A fruit in the strict botanical sense is the transformed gynoe- 

 cium after fertilization. 



From a single ovary results a simple fruit ; from several sepa- 

 rate ovaries of a flower is formed the aggregate fruit. From one 

 flower we have a single fruit ; from an inflorescence we get the 

 multiple or collective fruit (Ananas, multiple fruit ; cherry, simple 

 and single fruit; Ranunculus, aggregate fruit). 



Other parts of the flower besides the gynoecium may take part 

 in the formation of the fruit and form false fruits in distinction to 

 the true fruits defined above. Example : the receptacle of the 

 strawberry becomes fleshy and apparently represents the main 

 axis of the false fruit ; it is also an aggregate fruit, since many sepa- 

 rate ovaries (akenes) are situated upon the pulpy receptacle. The 

 apple is also a false fruit, since the hollow floral axis (cupuld) takes 

 part in its formation. The pappus-like developments on the fruits 

 of Composite are modifications of the calyx. 



Single fruits may be divided into five kinds: 1, capsule ; 2, 

 carpels; 3, achenium (akene) ; 4, drupe / 5, berry. (See figures 

 on p. 234.) 



1. The capsules open at maturity according to a fixed method. 

 They may be subdivided as follows. 



