THE BURBANK CHERRY 113 



Pollen which has previously been collected 

 upon a watch crystal from some open flowers is 

 applied by lightly touching the finger to it, then 

 to the stigma, taking care to cover the top of the 

 stigma completely with the pollen. 



This is a simple enough procedure, but it must 

 be done carefully, as the number of tests that 

 one experimenter can manage is limited. 



Moreover, it is necessary, of course, in a case 

 that calls for hand poUenizing, to mark the blos- 

 som with a tag of some sort, else there would be 

 no record of the experiment, and no way of tell- 

 ing whether it finally proved successful. Again, 

 it is usually desirable to remove other blossoms 

 from the cluster in which the artificially pollen- 

 ized one grows, to give a better opportunity for 

 development of this individual. 



If, finally, we are to make absolutely certain 

 that no other pollen comes in contact with the 

 stigma, thus guarding against the possibility of 

 fertilization of the flower by other pollen than 

 that intended, it may be desirable to tie a paper 

 bag over the flower. 



The latter procedure is not usually necessary, 

 particularly if care has been taken to cover the 

 stigma with pollen, as once this is dene there is 

 almost no danger that any foreign pollen will find 

 lodgment. ^loreover, the flower from which the 



