146 



AGRICULTURAL BOTANY 



the enlarged base, or ovary, the supporting column, 

 or style, and the flattened top, or stigma. In the 

 ovary are one or more small bodies, ovules, which will 



caly. 



FIG. 69. Calyx and Co- 

 rolla of Morning Glory. 



FIG. 70. Stamens. 

 a, filament; b, anther. 



stigma. 



develop into seeds under proper conditions. Not all 

 flowers are complete, sometimes one part and sometimes 

 another being wanting. 



Fertilization, or the process by which the ovule be- 

 comes transformed into life -bearing seed, 

 begins with the formation of pollen. 



Each grain of pollen is a single cell con- 

 taining protoplasm. During a certain 

 period the pollen grains from the anthers 

 readily cling to the surface of the stigma, 

 which is generally made moist by the se- 

 cretion of a sticky liquid. This process is 

 called pollination. The pollen grains thus 

 alighting send a slender tube through the 

 stigma and style to the ovule in the ovary. 

 Then, and not till then, occurs the trans- 

 formation of the dormant ovule in the ovary into active 

 life. This fertilized cell will now grow into a seed, 



ovary 



FIG. 71. Pistil 

 of Wild Gera- 

 nium. 



