548 HARRIS: OVULES AND SEEDS IN CERCIS 
In such cases the number of negative values is generally larger 
than the number of positive coefficients, and their mean numerical 
magnitude is always higher. For every large series examined the 
value of 7.2 has been over 2.5 times its probable error and some- 
times many times its probable error. These evidences can leave 
little doubt of the existence of a slight negative relationship 
between the number of ovules formed and the capacity of the 
. pod for maturing its ovules into seeds, the pods with the larger 
number of ovules producing relatively fewer seeds. 
This conclusion has also been reached in an earlier paper for 
the dwarf varieties of Phaseolus vulgaris as a whole. 
(e) The foregoing conclusions and other statements made in 
these pages apply exclusively to the one species considered and 
should not be extended to others except on the basis of actual 
data. There is ne reason to assume that species may not differ 
in this regard. The data available for another of the Leguminose, 
Robinia,* indicate that quite different conditions from those found 
in Cercis may prevail. If the correlations found for Sanguinariat 
are based on sufficiently large and representative samples they 
lead to the same conclusion. There are strong evidences that 
some strains of Phaseolus differ from others in the sign of this 
relationship. Indeed the Kansas series of Cercis differs rather 
conspicuously from others in the intensity of the negative corre- 
lation. 
The conclusions concerning capacity for seed development 
here drawn are based upon mature pods only. One of the most 
important things to be done is to determine the relation of this 
phenomenon to the intra-individual selective elimination of ovaries, 
if it occurs in Cercis. All of the data here discussed were col- 
lected before this differential failure of ovaries in Staphylea was 
demonstrated. As yet I have been unable to obtain adequate 
materials for solving the problem for Cercis. 
(f) This paper is exclusively a statement of observed facts. 
I have vo explanation to offer of the relationships which have been 
regularly found when adequately large series of data have been 
analyzed. Theories as to the causes underlying the conditions 
* Harris, J. Arthur. Biometrika 6: 441-442. 
: 1909. 
t Harris, J. Arthur. Biometrika 7: 321-324. 
I9Io. 
