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PLANT MORPHOLOGY. 
(/) POLLINATION AND FERTILIZATION. 
All the elements that we have thus far considered, 
namely, the gynoecium, androecium, corolla, calyx, 
bracts and nectar apparatus, play a role in the produc- 
tion of seed. The transferral of the pollen from the 
anther to the stigma and its subsequent germination 
constitute pollination. At the time that the ovules of 
the species to be pollinized have matured, the anthers 
ripen and discharge their pollen. When the pollen 
is discharged upon the stigma of the same flower the 
process is called close or “ self-pollination but when 
the pollen from one flower is carried to the stigma of 
another flower, by aid of the wind or water, or by 
animals, as insects and birds, or in other ways, the proc- 
ess is called “cross-pollination.” In the process of ger- 
mination the pollen grain develops a long tube-like 
process which penetrates the tissues of the stigma and 
style and, finally reaching the foramen of the ovule, it 
pushes its way through the cells of the nucellus to the 
embryo sac, where it discharges a cell known as the 
generative cell which unites with a cell in the embryo sac, 
known as the egg-cell. It is from the union of these 
two cells that the embryo develops, and this union of 
generative cells is known as fertilization, two kinds 
being distinguished, namely, “self-fertilization” and 
“ cross - fertilization,” depending upon whether self- 
pollination or cross-pollination has been effected. 
( g ) INNER MORPHOLOGY OF THE FLOWER. 
The inner morphology of the flower bears a close 
resemblance to the structure of the stem and leaf. The 
bracts in almost all particulars are like the foliage leaf 
of the same plant and the flower stalk closely resembles 
the foliage stem. The calyx, while resembling the foli- 
age leaf, usually contains calcium oxalate in greater 
