MUTATIONS 113 



Because the apricot has never been observed to arise direct 

 from the plum as the nectarine has repeatedly been known to arise 

 from the peach, and because the apricot trees have never been 

 known to bear plums as the nectarine trees occasionally bear 

 peaches, because of these facts botanists have quite generally 

 ceased to regard the apricot as a sport from the plum, and are 

 agreed, I believe, in considering it as a distinct species. 



However, it behaves precisely like a mutant, and in consider- 

 ing the means by which new types originate the presumptive 

 evidence is strong that the apricot originally sprang from the 

 plum stock. Though it is true that some mutations are fre- 

 quently repeated, it is also true that others arise but rarely. 

 The nectarine is unusual in the frequency with which it reap- 

 pears, and the readiness with which the peach and its mutant 

 exchange places has perhaps no parallel. 



In many respects the apricot appears like an intermediate 

 between the peach and the plum. The external appearance of 

 the fruit is that of the peach. The pit is smooth, resembling 

 that of the plum. The bark of the tree is like that of the peach, 

 but the leaf is like that of the plum. There is nothing to sug- 

 gest a hybrid origin, though everything to suggest that this 

 strange plant and its fruit are in some way composed of the 

 elements of both the peach and the plum. 



Nor would a hybrid origin be at all necessary to this fact. 

 Certain characters are general, running through many species 

 quite independent of consanguinity. Thus the weeping or the 

 cut-leaved habit is common to a great variety of species only 

 remotely related. The downy character is common with both 

 fruit and leaf, and almost every downy or pubescent species has 

 its glabrous or smooth variety, its mutant in all probability, 

 and one that easily and frequently arises. So also, without 

 doubt, the reverse is true by which smooth species occasionally 

 throw off downy or pubescent varieties. Now this particular 

 character of pubescence, while simple enough in itself, is yet 

 exceedingly noticeable, and serves to insure a specific name, 

 unless indeed the direct origin happens to be extremely well 

 known, in which case the mutant is likely to get off with a 

 varietal distinction. 



