56 FUNDAMENTALS OF AGRICULTURE. 



insects which might bring pollen. When the stigma 

 has become receptive, the bag is removed and pollen 

 applied from ripe stamens taken from the plant chosen 



V 



II 



ORANGE FLOWER BUD; MATURE ORANGE FLOWER; AN EMASCULATED 

 ORANGE FLOWER. 



a shows where anthers were detached. 



to be the other parent. The bag is again replaced 

 until development has proceeded so far that the stigma 

 is no longer receptive. If the two parents are closely 

 enough related seeds will be formed. The plants aris- 

 ing from these may resemble either parent or may be 

 intermediate. If they possess the characteristics 

 sought for and are capable of being propagated by 

 grafting or cuttings, etc., this can be done and the 

 work is accomplished. However, if they are of a 

 sort propagated by seed they are allowed to flower 

 and produce seed, of course excluding accidental pol- 

 lination from outside. 



Variation in the Second Generation. The plants 

 of the second generation are usually very variable, 

 showing all sorts of combinations of the various char- 

 acters of the parents, or they may resemble one or the 

 other of them. Those which show the desired com- 

 bination of characters are self-pollinated and their seed 

 sown again. Usually in the course of a few genera- 

 tions, the race becomes fixed and the characters per- 

 manent so long as pollination by some other variety is 

 prevented. 



EXERCISE. How would you improve the yield of corn on your 

 farm? How would you test the germinating power of seeds? 



