474 



FUNDAMENTALS OF FRUIT PRODUCTION 



in the size, form, color and odor of flowers docs not modify the funda- 

 mental processes which take place, following pollination, in the growth of 

 the pollen tube or in fertilization. In this discussion, therefore, but 

 little attention need be given to the structure of the so-called non- 

 essential flower organs. 



r^^ 





Plate I.— Successive stages in the development of the ovule of the orange. In Figure 

 1, mm = macrospore, u = inner integument, and oi = outer integument. Figs. 2 and 3, 

 later stages in which the integument more nearly encloses the nucellus. Fig. 4, the fully 

 developed embryo sac, showing the egg apparatus at the upper end, the polar bodies near 

 the center, the antipodals at the bottom. Fig. 5, the embryo sac after fertilization, one 

 of the synergids (pO disintegrating, the egg cell at oo, and 8 endosperm nuclei (e7i)- {After 



