48 LUTHER BURBANK 



economize in the shell covering of her egg in case 

 lime is lacking in her food. 



The same sort of economy is practiced when 

 the human child finds inadequate nourishment. 

 In such case the bones may be not only small but 

 defective in mineral substance, a well-recognized 

 type of abnormality resulting with which med- 

 ical men are familiar. 



So it seems plausible that a paucity of proper 

 food materials was the explanation of the origin 

 of the original Sans Noyau. 



It is in keeping with this explanation that the 

 Sans Noyau is, as we have seen, a small scraggly 

 shrub, a mere dwarf as compared with the aver- 

 age stature of trees of its family; and that its 

 fruit is reduced to the proportions of a small 

 berry, and is utterly lacking in those qualities of 

 sweetness and flavor that are the almost universal 

 characteristic of other stone fruits. 



In a word, then, it is highly probable that the 

 plum that supplied the character of stonelessness, 

 upon which my experimental endeavors in the 

 production of a marketable stoneless plum was 

 founded, was a pathological product. 



I may add that many other "sports" or muta- 

 tions in the vegetable world that have furnished 

 a basis for the evolution of new races or species 

 may very probably have had the same origin. 



