174 BROOKLYN BOTANIC GARDEN MEMOIRS 
Notwithstanding these two sources of difficulty in basing con- 
clusions on relative amount of dry substance, there seem clear evi- 
dences that the abnormal plants produce relatively as well as abso- 
lutely less dry matter than the normals. 
In the case of the primordial leaves, there are 20 samples in which 
the relative dry weight is lower in the abnormal plants as against 3 in 
which it is higher. In the first compound leaf there are 15 samples 
in which the relative weight in the abnormal plants is lower, as com- 
pared with 8 in which it is higher than the normals. 
The average percentage content of dry substance in the primordial 
leaves of the abnormal seedlings is 6.509 as compared with 6.779 in 
the normal controls, or a difference of —0.270. The average percent 
of dry matter in the first compound leaf is 8.030 in the abnormal as 
compared with 8.080 in the normal, or a difference of —.050 percent. 
CONCLUDING REMARKS 
The constants recorded in this paper are the results of one of the 
phases of an attempt to determine the nature of the relationship 
between morphological and physiological variations in plants. 
The results of the criteria applied are beautifully clear and con- 
sistent. 
Seedlings of Phaseolus which show one of the smallest definite 
structural variations, the slight vertical separation of the two coty- 
ledons in their insertion on the axis, are differentiated from.the struc- 
turally apparently normal individuals in their physiological as well 
as in their morphological characteristics. 
This is shown by the facts that the morphologically abnormal 
plants produce a smaller weight of green leaf tissue, a smaller actual 
weight of dry substance in the leaf tissue, and a smaller relative weight 
of dry substance. This is true for both the primordial leaves and 
the first trifoliate leaf. 
