40 STATE HOETICULTURAL SOCIETY. 



pollen from an earlier or a later flower. Frequently the pistil is longer 

 than the stamens and reaches above them out of reach of their pollen- 

 In other cases the stamens and pistils are borne on separate plants as 

 is the case in some of our cultivated strawberries. In such cases 

 cross-fertilization must always be the result. Sometimes the pollen of 

 a certain plant is entirely impotent upon the pistils of that plant. Many 

 of our wild plums are of this class. Frequent instances are cited where 

 plum trees producing an abundance of pollen failed to set fruit until a 

 tree of another variety was set among them, when they produced 

 abundantly through the perfect potency of the new supply of pollen. 



Certain plants are dependent upon one or more species of insects 

 for the fertilization of its flowers. Our native yuccas being dependent 

 upon a single species of moth to perform this function, is a most re- 

 markable example. A complete account of the life history of this in- 

 sect and its remarkable habits in securing the fertilization of the yuccas, 

 may be found in the reports of the Missouri Botanical Garden. 



For a long time it has been well known that the fig is dependent 

 upon a certain fly for its perfect fertilization, and that when the pollen 

 is carried from flower to flower by the insect, the fruit is much larger 

 and of more delicious flavor than when the flowers are fertilized through 

 any other agency. 



Cultivators of strawberries express a preference for certain varie- 

 ties of pollinators of the various pistillate sorts. This preference is 

 founded upon the fact that the pollen of some staminate varieties is 

 prepotent as compared with that of certain other varieties which flower 

 at the same Time. It is a commonly noted fact that most pistillate 

 varieties produce finer fruit than the staminate sorts. One reason 

 given for this is that the pistillate sorts must always be cross-fertilized. 



Since cross-fertilization, as thus far discussed, refers primarily to 

 the crossing of plants of the same species, it may not be amiss to men- 

 tion briefly the subject of hybridization, or crossing of two different 

 species. Without going into a lengthy discussion of this subject, it 

 may be stated that in the vegetable as well as the animal kingdom there 

 are few undoubted hybrids. Experiments in the hybridization of plants 

 has generally proven barren of beneficial results. Where hybrids are 

 not actually sterile, it has been shown to be difficult, in most cases, to 

 fix a type in their offspring. 



Finally we may conclude that where cross fertilization between 

 different varieties is favored, we may expect the most beneficial results. 

 Insects are the active agents through which cross-pollination is best 

 effected. Experiment may yet prove the comparative value of different 



