52 Bog-Trotting for OrcKids 



Darwin believed that, ' ' bearing also in mind the larger 

 number of species in man}^ parts of the world which 

 from this same cause are seldom impregnated, we are 

 led to believe that the self- fertilized plants formerly de- 

 pended on the visits of insects for their fertilization, 

 and that, from such visits failing, they did not yield a 

 sufiiciency of seed and were verging towards extinction. 

 Under these circumstances, it is probable that they 

 were gradually modified, so as to become more or less 

 completely self-fertile; for it would manifestly be more 

 advantageous to a plant to produce self-fertilized seeds 

 rather than none at all or extremely few seeds." ' 



Darwin questions: " Whether any species which is 

 now never cross-fertilized will be able to resist the evil 

 effects of long-continued self-fertilization, so as to sur- 

 vive for as long an average period as the other species 

 of the same genera which are habitually cross-fertilized, 

 cannot of course be told. . . . It is indeed possible 

 that these self-fertile species may revert in the course 

 of time to what was undoubtedly their pristine con- 

 dition, and in this case their various adaptations for 

 cross- fertilization would be again brought into action." ° 



Indeed, the more this great scientist studied these 

 strange flowers, the more he became impressed, and 

 " with ever-increasing force, that the contrivances 

 and beautiful adaptations slowly acquired through each 

 part occasionally varying in a slight degree but in 

 many ways, with the preservation of those variations 

 which were beneficial to the organism under complex 



^ 'Davw'm, Fertilization of Orchids,-^. 2C)2. 1895. ''Ibid. 



