LUTHER BURBANK 



We shall have early-bearers that are of good 

 size and taste, but lack shipping quality; other 

 early-bearers that are good shippers but lack size 

 or taste; yet other specimens that have size and 

 taste and shipping quality, but lack the quality of 

 early bearing; and so on throughout all the possi- 

 ble combinations of five pairs of qualities. 



But the combination of all the desired char- 

 acters in a single individual will take place very 

 rarely indeed. 



And when we advance from five pairs of unit 

 characters to ten or twelve, as we have already 

 seen that we must do in the case of our cherry, 

 the matter becomes almost infinitely complex. As 

 we increase the number of qualities under consid- 

 eration, the number of possible combinations 

 among them increases at an alarming geometrical 

 ratio. 



It appears that whereas there is an even 

 chance, when only a single pair of qualities was 

 in question, of producing one offspring like each 

 parent in each group of four; and whereas there 

 is the same even chance of producing one off- 

 spring like each parent in every group of 256 

 individuals when four pairs of unit characters are 

 in question — when we have to deal with ten pairs 

 of unit characters the possible arrangements have 

 become so bewildering and complex that there is 



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