236 THE SURVIVAL OP THE UNLIKE. [x. 



same authority, contain 4.7 per cent of sugar and 1.3 

 per cent of free acid, while wild ones contain 3.5 per 

 cent of sugar and 1.9 of acid. Parsons* finds that 

 sugar increases rapidly in oranges as they depart from 

 the wild types, although free acids do not show a cor- 

 responding decrease. Thus the wild Bitter-sweet of 

 Florida contains .84 per cent of cane sugar and 5.71 

 of glucose ; and the sour orange .97 cane sugar and 

 3.36 glucose ; the common oranges, 4.38 and 4.60 re- 

 spectively ; russets, 4.51 and 7.29 ; mandarin, 8.07 and 

 4.77. The figures and experiences uniformly show 

 that amelioration and sweetness go hand in hand ; 

 and every one who has tested seedling or wilding fruits 

 can bear testimony to the same fact. 



As a matter of experience, seeds of small or low- 

 colored fruits, or from tender or unproductive varie- 

 ties, do not give a larger proportion of varieties of 

 high quality than seeds from large, highly colored and 

 vigorous kinds. And it is worthy of remark that 

 while most pomologists hold to the correlation of 

 quality with decrease of other characters, they at the 

 same time recommend that in producing new vari- 

 eties only seed from the largest, finest and har- 

 diest varieties should be used. 



It is evident, from our discussion, that quality and 

 other characters of cultivated fruits appear indepen- 

 dently of each other, — that there is no true correlation 

 between these characters. There is a general increase 

 in all characters as amelioration progresses, at least 

 in all characters which are sought by horticulturists ; 

 and this fact must ever remain the chief inspiration 

 to man in his efforts to ameliorate plants. 



♦Ajtric. Science, iii. 23. 



