CHAPTER VII. 



CROSS AND SELF-FERTILIZATION IN PLANTS. 



Dr. Gray, in that charming little book, 



Cross Fertilization, jju th ^ t) u v u/^i 



How Jrlants Behave," says: "Close 



fertilization, that is, the fertilization of the seeds by pollen 

 from the same flower is very close breedins; indeed. It is 

 the next thing to no fertilization at all in plants, that is to 

 propagation by buds." From an elaborate series of experi- 

 ments madfe by Darwin ^ supplemented by the work of 

 others ^, there can no longer be any doubt that cross-fertiliza- 

 tion is an advantage. Darwin has aptly said, "Nature abhors 

 perpetual self-fertilization." l^ince the appearance of Dar- 

 win's Fertilization of Orchids manv contributions have been 

 made to show the exquisite relations between flowers and 

 insectsj Most observers agree that the structure of many 

 flowers is for the purpose of securing cross-fertilization and 

 to avoid self-fertilization, although there are those who are 

 unwilling to see the utility in cross-fertilization. Thomas 

 Meehan ^, says. "It has never been clear to my mind that 

 insects are any material aid to plants by the pollination 

 which they often undoubtedly accomplish. There has been 

 little to prove that in-an-in, or close breeding, is an injury; 



1 Cross and self-fertilization in plants. See also different forms of flowers 

 in the same species. Fertilization or orchids. 



S Hildebrand : Die geschlechter vertheilung bei den pflanzen, etc. 

 Mueller: Fertilization of flowers, English translation. 

 Lubbuck; British wild flowers in relation to insects, etc. 

 3 On the ferfcilizationlof Cassia marylandica, Proc. Academy of Natural 

 Sciences. Philadelphia, Aug. 31, 1886, p. 314. 



