HARRIS: INTERRELATIONSHIP IN PHASEOLUS 



173 



Having shown that the abnormal plants produce both a smaller 

 green weight and a smaller dry weight in both the primordial and in 

 the first compound leaves, the problem of the relative quantities of 

 water and dry materials in the leaves of the two types of plants 

 naturally presents itself for consideration. 



The results have been expressed in terms of the percentage of dry 

 substance in the leaves, i. e. (dry weight X 100) /green weight. The 

 constants appear in Table III. 



TABLE III 

 Percent of Dry Matter in Primordial Leates and in First Compound Leaf 



The results are not so consistent as those for the absolute values, 

 green weight and dry weight. This condition is to be expected for 

 two reasons. First, the abnormal plants show lower values of both 

 green weight and dry weight than the normal controls. One cannot, 

 therefore, expect such large differences in the indices calculated from 

 these constants as if both measures did not differ in the same direction 

 between abnormal and control series. Second, two sets of technical 

 operations are involved in the indices, only one in each of the con 

 stants used in calculating these ratios. While every effort to avoid 

 error was made, the probabilities of error in an index are clearly 

 twice as great as in either of the constants upon which it is based. 



