404 CONDITIONS FAVORABLE TO HYBRIDIZATION. 



has not become quite inoperative. Some days 

 elapse before any other signs of fecundation ap- 

 pear after the fall of the corolla, such as the en- 

 largement of the peduncle, or strengthening of its 

 articulation, and that period seems to him longer in 

 hybrid impregnation, as well as the interval before 

 the seeds are vivified. Both he and Kolreuter 

 observe instances, such as I have found, of false 

 hybrid impregnation, producing an enlargement of 

 the germen, or even seeds with an imperfect embryo, 

 or without any. They remarked that they did not 

 usually obtain the full complement of seeds from a 

 hybrid impregnation, unless the affinity was very 

 close. My own observation is that this circumstance 

 depends rather on similarity of constitution." 



The art of hybridization can be used not only in- 

 the production of new sorts by crossing different 

 species, but its results are generally of more prac- 

 tical value, as applied to crossing the different 

 seminal varieties of the same species. 



When two plants are to be hybridized, it is im- 

 portant that both the stigma and the pollen be in a 

 state to act upon each other immediately. All 

 anthers should be taken off from the flower which 

 is to be acted upon, so that its pollen can not an- 

 ticipate the action of the foreign grains, and they 

 must therefore be removed before they have ap- 

 proached the time of dehiscence. To do this it 

 will be necessary to open the corolla, and cut these 



