THE SELF-FERTILIZATION OF PLANTS. 343 



whilst growing in their native country, under natural 

 conditions, cannot be fertilized with pollen from the 

 same plant. They are sometimes so utterly impotent, 

 that though they can readily be fertilized by the pollen 

 of a distinct species, or even distinct genus, yet wonder- 

 ful as the fact is, they never produce a single seed by 

 their own pollen. In some races, moreover, the plant's 

 own pollen and stigma mutually act on each other, in 

 a deleterious manner." 



In all of these plants, so self-impotent, and of injuri- 

 ous self-action, there are to be found many of the 

 organs reduced to a rudimentary condition ; in some 

 cases, with the rudiments still traceable ; and, in others, 

 with not, as Darwin shows, a single vestige of the lost 

 characters, discernible. 



Darwin fancies, that these parts which are wholly 

 lost, and these rudimentary parts, have " first become 

 of less and less use and then absolutely valueless." 

 But, valueless as he may esteem them, they, by their 

 absence, work serious effects upon the constitution, 

 and upon the capacity of the reproductive elements, 

 which can never regain their full potency and vigor, 

 until these lost and rudimentary characters are fully 

 re-developed. The perfect type alone, is consistent 

 with physiological integrity ; and, the various degrees 

 of lessened fertility and of sterility, which are empiri- 

 cally noted by Darwin, are but the registers of the 

 several degrees of departure from such type. 



Even in Plants, seemingly very much alike, there 

 are positive differences which, if united in an indi- 

 vidual, or united in the reproductive elements, will 

 frequently, where the parents are but little prolific, 



