ORIGINATING NEW VARIETIES. 149 



part, the style, joined to a round, greenish body, the ovary, 

 at its base. This ovary, when fully developed, forms the 

 fruit. If we cut through the ovary from top to bottom 

 with a sharp knife and examine the section with a hand- 

 lens, a number of small, light-colored bodies, attached 

 along the central column, may be made out. These are 

 the ovules (Fig. 35, O.), which, after being fertilized, grow 

 and form the seed. The stamens and pistil are called the 

 essential organs of the flower, because they are the parts 

 which form the seed for the reproduction of the tree. It 

 is with them that one making crosses is most concerned, 

 for through their agency seed is produced and through 

 them only can the work be done. 



As already indicated the ovary grows and forms the 

 fruit while the ovules develop into the seed. But seed-form- 

 ation does not commence until the ovules are acted upon 

 by the pollen. When the anthers are ripe the pollen is 

 discharged through slits in the sides. The stigma must 

 also ripen or become receptive to the pollen. This condi- 

 tion in citrus flowers is shown by its viscid appearance and 

 by its being covered with a whitish, sticky fluid. Then if 

 the pollen be placed upon the stigma it is held there by 

 the adhesive surface and germinates, each pollen grain 

 sending out a little slender tube, which grows through the 

 style and finds its way into the ovary, where the contents 

 are emptied into the ovules. Then fertilization or fecunda- 

 tion is accomplished and seed-development begins. 



MODE OF OPERATION. 



Having now become acquainted with the different 

 parts of the citrus flower and their uses, the operator is 

 ready for the actual work. 



If any considerable amount of pollination, i. e., trans 



