26 STATE BOAKD OK HORTICULTURE. 



the end of three weeks from budding, the wr<apper has to he 

 removed and the buds examined with a magnifying glass. If 

 the union is complete at the crown of the germ return the 

 wrapper, to exclude sun and air until the bud starts to grow. 

 Sometimes only one-half of the bud starts to grow; all such 

 should be cut out and the budding done over again. Sometimes 

 both halves die, or both halves grow separately. Then it has 

 to be done over again on a new place in the stock. There 

 ought to be at least fifty buds of each combination put in at 

 the same time to cover failures." 



Mr. Thomson has distributed a great many buds and trees 

 among his neighbors and in other sections of the State. The 

 trees have invariably continued to produce a thin-skinned 

 orange and seemingly remaining constant. Many have claimed 

 that the variety has not produced fruit as grown on the original 

 trees, but Mr. Thomson says this has not been on trees which 

 he has supplied. The buds then must have come from other 

 trees that are not the true "Improved Navel." 



METHODS USED IN HYBRIDIZING PLANTS.* 



The process of hybridizing plants is in itself neither difficult 

 nor mysterious, it being simply necessary to understand the 

 general structure of the flower to be used. The flowers of the 

 tomato, pear, and orange may be taken as illustrating the 

 common forms, although, of course, very many modifications 

 occur. The envelopes of these flowers, as in the case of the 

 flowers of most cultivated plants, consist of two whorls of 

 modified leaves. The outer whorl, which is known as the 

 calyx, is commonly green like the foliage and is divided into 

 several distinct or more or less united lobes, or sepals; while the 

 inner whorl, or corolla, is usually of some bright color other 

 than green, and its different divisions or lobes are known as 

 petals. In some cases, as in the lily, the calyx and corolla 

 are of the same color, so that they are not easily distinguish- 

 able; while in still other cases, as in oaks, walnuts, etc., the 

 corolla is entirely wanting. 



The essential, or sexual, organs of the flower, the stamens 



* By Walter T. Swingle and Herbert ,J. Webber, Special Agents Department 

 ol Agriculture. Yearbook 1897, p. 38.5. 



