CHAPTER VII. 

 POLLINATION AND FECUNDATION. 



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1. It is necessary that the ripe pollen, which is produced in 

 the anther, be deposited upon the mature stigma ; otherwise no 

 seeds will be produced. The transference of the pollen is 

 called Pollination,' a process that is effected by several agen- 

 cies and aided by numerous contrivances. When both the 

 essential organs (stamens and pistils) are contained in one and 

 the same flower, as the Rose, Lily, Buttercup, Mint and Grass, 

 it is called a hermaphrodite flower. Many plants possess, 

 either in the same cluster or on different branchlets, both fer- 

 tile (or pistillate) and sterile (or staminate) flowers, and they are 

 said to be monoecious (Gr. monos, one ; oikos, house) ; such are 

 the Oaks, Hickories, Alder, Corn, Nettle, etc. Others have the 

 fertile and sterile flowers on different trees, as the Willows, 

 Poplars, Ash, Hemp, etc., and they are described as dioecious 

 (Gr. di, two ; oikos, house). In monoecious and dioecious plants 

 it is evident that the transport of the pollen from the staminate 

 to the pistillate flowers must in some way be effected in order 

 to accomplish fecundation. Even in hermaphrodite flowers it 

 is rarely the case that the pollen, wholly unaided, falls on the 

 stigma of the same flower. 



The topics treated in this chapter call for observation in the field, as well as 

 careful study at the table in the class-room. The structures that are directly 

 or indirectly concerned in pollination must not only be studied anatomically 



• The term " fertilization " has been used to indicate the transference of 

 pollen as well as to denote the fecundation which follows. To fertilize is to fur- 

 nish nourishment and it is best to use the word only in that sense. For the 

 terms self-fertilization and cross-fertilization used in Darwin's writings and 

 elsewhere, the words self-pollination and cross-pollination may be substituted. 

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