52 Bog-Trotting for Orchids 



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

 number of species in many 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 faihng, they did not yield a 

 sufficiency 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-fertihzed 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 



' Darwin, Fertilization of Orchids, p. 292. 1895. '^ Ibid. 



