426 
AMERICAN JOURNAL OF BOTANY 
[Vol. 8. 
Lack of space precludes the publication of the 30 individual correlation 
tables upon which the coefficients discussed in this section are based. These 
may, however, be easily formed from the schedules showing the formula 
for the basal bundles in other papers of this series.^ 
Table i. Correlation between Number of Primary Double Bundles and Number of 
Intercalary Bundles at Base of Hypocotyl 
Line 
Trimerous 
Dimerous 
Difference 
Diff. 
£diff. 
N 
r 
r 
N 
r 
r 
Er 
75 
142 
— .5004^.0424 
11.8 
142 
-.ii77±.0558 
2. II 
— .3827 ±.0700 
546 
93 
155 
-.6155 ±.0337 
18.3 
155 
-.1449 ±.0530 
2.73 
— .4706 ±.0624 
7.54 
98 
183 
— .6515 ±.0286 
22.8 
183 
+ .0643 zb. 0496 
1.30 
-.7158^.0574 
12.4 
139 
106 
-.5053 ±.0488 
10.4 
305 
+.1364 ±.0379 
3.60 
— .6417 dz. 0618 
6.0 
143 
221 
— .3184^.0408 
7.8 
420 
+.0338db.0329 
1.03 
-.3522 ±.0530 
5-4 
Analysis of Data 
I. Relationship between Number of Primary Double Bundles and Number 
of Intercalary Bundles. We shall first consider the relationship between 
the number of primary double bundles and the number of intercalary 
bundles at the base of the hypocotyl in dimerous and trimerous plants. 
The correlation coefficients for the five lines appear in table i. For 
the trimerous plants of all five lines the correlations are negative in sign, 
i.e., the number of intercalary bundles is greater in plants which have a 
smaller number of primary double bundles, and vice versa. For dimerous 
plants three of the five lines show a slightly negative coefficient, but two 
show a low positive correlation. The constants indicate that the corre- 
lations for the trimerous plants are much higher numerically than those 
for the dimerous plants. Those for the trimerous are of the order —.3 
to —.6 while those for dimerous plants are sensibly zero, averaging + .005. 
The correlations for the trimerous plants are in all cases several times as 
large as their probable errors, while those for the dimerous plants could 
hardly be regarded as statistically significant if only one of the lines were 
available. The differences, taken with regard to sign, between the corre- 
lations for the dimerous and trimerous plants are in each case significant 
in comparison with their probable errors. 
Expressing these results in terms of regression we have the following 
equations: 
4 The entries to be selected from the pubHshed tables can be determined from the values 
of N. In lines in which true siblings were available (75, 93, and 98) only siblings have been 
used, even though additional sections of one or the other type were available. In the two 
lines in which random samples of seed were used for the production of the dimerous and 
trimerous seedlings, the largest possible number of individuals available in the tables of the 
papers cited was employed for the constants here discussed. ' 
