NEW PARTS DEVELOPED BY FRUCTIFICATION 103 



Parts Useless in Fructification. — The only portion of the flower which 

 is certain to be in no case utilized in fructification, and, therefore, to 

 disappear after fertilization, is the actual stigma, and the stamens when 

 they are non-adherent. The stamens, as has been shown, may be ser- 

 viceable for other purposes, so that their death depends rather upon 

 the performance of their individual function than upon fertilization. 

 In proterogynous flowers this function is actually stimulated by the 

 completion of fertilization in their own flower. 



Parts Useful in Fructification. — Upon the other hand, we are not 

 certain of a requisition in every case for the preservation and develop- 

 ment of any part other than the particular ovules which become fer- 

 tilized, the ovarian walls of the pistil or pistils containing them (and 

 in some cases only a part of these), and of the torus. The death or 

 decay, therefore, of any or all of the other parts will be determined by 

 the individual or class habit of the plant concerned. 



Accrescent Parts. — To any part other than the ovary, which thu^ 

 develops and enlarges as a part of the fruit, the term Accrescent isl 

 apphed. 



Accessory Fruits. — Fruits of which such accrescent parts form the 

 conspicuous portion are called Accessory fruits. 



New Parts Developed by Fructification. — Finally, we must note that 

 new parts, of service in the fruit, frequently develop in the course of 

 fructification, upon either pericarp or seeds, just as special appendages 

 develop upon the floral organs for performing special function in con- 

 nection with pollination. That such additional parts exhibit little, if 

 any, development during the floral stage, is due to the fact that an 

 enormous waste of energy on the part of the plant would thus be 

 involved. Of all the flowers produced by a plant, only a minor portion 

 usually accomplish fructification, and of all the ovules produced by any 

 gynaecium only a minor portion usually produce seeds. The develop- 

 ment of these superfluous flowers and ovules constitutes in itself a 

 serious waste, but it is a necessary or, upon the whole, an economical 

 one, as it tends in the end to secure the full degree of fructification by 

 the plant. The development, however, upon such superfluous flowers 

 or ovules, of parts which will be of value only in case fructification is 

 effected, would be anything but economical. Hence the general 

 rule that parts of the fruit which are of no use in effecting poUination 

 and fertihzation are not developed until after these functions are 

 performed. 



