July, 1921] THE SEEDLING OF PHASEOLUS VULGARIS 
353 
Table 4. Differences between correlations for three classes of bundles at base of hypocotyl 
and the number of bundles in the central regions of hypocotyl and epicotyl, respectively 
Character of Seedlings 
Rnd Line 
Trimerous 
Line 75 
-.325±.o74 
4-39 
-.203±.075 
2.71 
— .467^.064 
7.29 
Line 93 
-.320=b.o74 
4-32 
-.259±.075 
3.45 
-.6i7=t.o68 
9.07 
Line 98 
-.313^.067 
4.67 
-.i83±.o69 
2.65 
-.487 ±.059 
8.25 
— .522 dr. 084 
6.21 
— .081 ±.092 
0.88 
-.626±.o8o 
7.83 
Line 143 
-.538±.055 
9.78 
-.072 ±.059 
1.22 
-.563 ±.048 
11.7 
Dimerous 
Line 75 
-.477±.o7o 
6.81 
-.711^.065 
10.9 
-.841^.059 
14.3 
Line 93 
-.557±.o62 
8.98 
— .258zb.070 
3.69 
-.586±.057 
10.3 
Line 98 
-.427±.o55 
7.76 
— .446zh.o6o 
743 
-.581 ±.052 
II. 2 
Line 139 
— .i8ozb.05i 
3-53 
-.753±.039 
19-3 
-.750^-037 
20.3 
Line 143 
— .5i8±.040 
12.9 
-.500±.037 
13-5 
-.681 ±.033 
20.6 
epicotyl of the plant. The correlation surfaces are given in tables A-L. 
The results are set forth in table 5. 
Table 5. Coefficient of correlation between number of bundles in central region of hypocotyl 
and central region of epicotyl 
Line 
Trimerous 
Dimerous 
N 
r 
r/Er 
N 
r 
rIEr 
75 
416 
+ .oi2d=.033 
0.36 
416 
-.oi7±.033 
0.52 
93 
557 
+.075±.028 
2.68 
557 
+ .l62±.028 
5.79 
98 
345 
+ .090 ±.036 
2.50 
345 
+ .225±.035 
6.43 
139 
106 
— .061 ±.065 
0.94 
305 
-.i87±.037 
5.05 
143 
143 
+.256±.042 
6.10 
420 
+.107 ±.033 
3-24 
The correlations are positive with the exception of that for dimerous 
plants of line 75 and of that for both dimerous and trimerous plants of 
line 139, which are negative in sign. Only one of the negative coefficients 
may be considered statistically significant in comparison with its probable 
error. Several of the positive coefficients are large enough in comparison 
with their probable errors to be considered possibly significant. The 
average correlation for the trimerous plants is +.074 while that for the 
dimerous plants is +.058. The correlations for the trimerous and dimerous 
plants can not be considered to differ significantly. 
The generally positive sign of the constants suggests that seedlings 
which have a larger number of bundles in the hypocotyl have on the average 
a larger number of bundles in the epicotyl. This is the condition actually 
found in the series studied, but the difficulties in the interpretation of the 
probable error in cases in which the correlation coefficient is so small should 
make one cautious in generalizing the results obtained. 
How slight the relationship between the numbers of bundles in the two 
organs is, may be shown by the regression lines giving the change in the 
mean number of bundles in the epicotyl associated with variations in the 
