21G THE FLOWER. 







397. The subject, here considered as a part of morphology, 

 must be fully treated, as regards acts and processes, under ).h\ Bi- 

 ology. Every thing in the flower is in relation to fertilization 

 and fructification, directly or indirectly. This section is con- 

 cerned with those adaptations of structure by means of which 

 agents external to the blossom are brought into service for its 

 fertilization. 



39<s. Liniiieus and his successors taught that the adjustments 

 in hermaphrodite flowers were such, on the whole, as to secure the 

 application of the pollen of its stamens to the stigma of its pistil 

 or pistils. The present view is, that this is doubtless strictly 

 secured in certain flowers of a moderate number of species, but 

 never in all the flowers of any such species ; that in ordinary 

 flowers, where it may commonly take place, it is not universal ; 

 that in the larger number of species there is something or other 

 in the floral structure which impedes or prevents it. Some 

 flowers are adapted for close fertilization ; some for cross fertili- 

 zation ; some for either. Here two terms need definition, viz. : 



Close fertilization or Self-fertilization^ or Autogamy, the applica- 

 tion and action of a flower's pollen upon its own pistil ; 



Cross fertilization, or Allogamy, the action of the pollen of one 

 flower on the pistil of some other flower of the same species. 

 This may be near, as when between flowers borne in the same 

 cluster or on the same plant ; remote, when between flowers of 

 distinct plants of the same immediate parentage ; most remote, 

 when between different races of the same species. Anything 

 beyond this is hybridization, or crossing of species. 



2. ADAPTATIONS FOR ALLOGAMY OR INTERCROSSING. 



399. The doctrine now maintained appears to have been first 

 propounded by Sprengel in the statement that "Nature seems 

 to have wished that no flower should he fertilized by its own 

 pollen." -a proposition which is not wholly tenable, for there 

 are blossoms specially adapted to self-fertilization. It was re- 

 affirmed in oiii- day by Darwin, in a similar adage. " Nature 

 abhors perpetual self-fertilization." -a metaphorical expression 

 to which no eil'ective exception has been taken. And the infer- 

 ence was drawn by him, that some important good to the species 

 must result from propagation through the union of distinct 

 individuals, and especially of individuals which have been dis- 

 tinct for several or many generations. 



bending Geitonogamy, fertilization by pollen of otber flowers of the same 

 plant, and Xenogamy, by pollen from a flower on another plant. 



