CONCLUSION. 39 



That tobacco and tomato plants sometimes set and ripen fruits with- 

 out the flowers having received any pollen, and that such fruits con- 

 tain no germinative seeds; 



That but few fruits will be obtained by the pollination of immature 

 cotton and tomato pistils, but that good percentages may be obtained 

 if the pollination is performed when the pistils are receptive. 



The lesson taught by these experiments is that some flowers can not 

 be successfully pollinated when the work of emasculation is per- 

 formed, while others can. and that no arbitrary mode of procedure 

 can be given for all flowers. A study of the behavior of each kind of 

 flower will reveal its peculiarities and its requirements, and. under- 

 standing these, hand-pollinations should lie highly successful. 



