160 BOTANICAL GAZETTE [SEPTEMBER 
in the seedlings of this extremely abnormal race is shown in com- 
parison with the normal control plants in table III. The results 
are self-explanatory. Without exception, in the twenty-three 
samples representing weighings of 9958 leaves of abnormal and 
4668 leaves of normal plants, the percentage of dry matter is lower 
in the abnormal than in the control series. A study of the averages 
for the individual groups of seedlings, classified with respect to 
primordial leaf number, does not suggest a significant difference in 
the percentage of dry matter in the different classes of seedlings. 
Probably a far larger series of weighings would be required to 
bring out such a differentiation if it exists at all. 
TOTAL WEIGHT OF EPICOTYLEDONARY TISSUE IN FLANTS OF 
TERATOLOGICAL AND NORMAL RACES.—In the foregoing discussion 
comparisons were limited to the weight of primordial leaves. This 
was done because of the difficulty of securing leaves subsequently 
formed in comparable stages of development in the normal and 
teratological seedlings. It seemed desirable to supplement these 
studies by the determination of the total weight of tissue produced 
by the two races. The results for a comparison of the total weight 
of tissue produced above the cotyledonary node by tetracotyle- 
donous plants and their normal control of line 139, are shown under 
the heading ‘‘epicotyl”’ in the fundamental tables of data. 
The constants show that without exception the green weight and 
dry weight per plant and percentage dry matter are higher in the 
normal than in the tetracotyledonous plants. The percentage 
differences range from —7.6 to —29.4 in the case of green weight, 
and from —10.1 to —30.5 in the case of dry weight. The differ- 
ences in percentage of dry matter range from —0.036 to —0.249. 
The average weight of green tissue per plant is 1.4447 for the 
abnormal and 1 .8088 for the control series, or a difference of —o . 3640 
gm. The average.dry weight per plant is 0.1093 for the abnormal 
and o.1384 for the normal seedling, or a difference of —o.0291 gm. 
The average percentage difference for the green weight is — 18.96, 
while for dry weight the difference is —20.30. The percentage of 
dry material in the abnormal seedling is 7.6448 as compared with 
7.7740 in the control, a difference of —o.1292. 
