178 LUTHER BURBANK 



shaped, and some of them had rough and cor- 

 rugated scalelike surfaces, suggesting the skin 

 of a lizard rather than that of a potato. More- 

 over, they were bitter in flavor and utterly un- 

 like the ordinary potato in taste. They further 

 showed their departure from the traditions of 

 their kind by manifesting a tendency to sprout 

 even while the tomato top was still growing 

 vigorously. 



Perhaps these results, as regards both the 

 relative normality of the tomatoes borne by the 

 grafted vine, and the abnormality of the pota- 

 toes grown by the roots, might have been ex- 

 pected. At least they seemed quite explicable. 



It will be recalled that the conditions of plant 

 growth were detailed somewhat at length in the 

 first chapter of the present volume, and that it 

 was there pointed out that the plant roots absorb 

 from the soil about them mineral salts in solution 

 that are carried up to the leaves of the plant be- 

 fore they are transformed into organic matter 

 by combination with carbon drawn from the air. 

 It was noted that the organic compounds thus 

 manufactured in the leaves of the plant must be 

 sent back down the stem of the plant to be de- 

 posited, in case of a tuber- forming plant like the 

 potato, in connection with the roots in the 

 ground. 



