410 
J. ARTHUR HARRIS 
By all available tests the coefficients for pods per plant and ovules per 
pod seem to be significantly higher than those for pods per plant and 
seeds per pod. 
(3) As a resultant of the relationship between pods per plant and 
ovules per pod (rpo) and that demonstrated elsewhere between ovules 
and seeds per pod (ros) some correlation must be expected between 
number of pods per plant and number of seeds per pod, whether there 
be any direct physiological interdependence between these two charac- 
ters or not. 
(4) By determining the correlation between p and 5 for constant 
values of 0, i, e. by calculating oTps by the usual partial correlation 
formulae for three variables, I have tried to remove the influence of 
the interrelationships oi 0, p and 5 upon the coefficient rps. 
(5) All the coefficients measuring the relationship between number 
of pods and number of seeds are lowered by thus correcting for rpo and 
ros, that is orps < rps, always. Several of the partial correlations have 
the negative sign. Their mean value while very small, orps = -f .051, 
is apparently significantly positive. 
(6) Thus on the average, there is some correlation between the 
numbers of pods per plant and the number of ovules which develop 
into seeds which is in part at least independent of — although it may 
be inseparably- bound up with — the morphogenetic factors which link 
together the magnitudes of the two characters p and 0. This corre- 
lation which must have its origin in the factors underlying the fertili- 
zation of the ovule and its nutrition during the period of growth into a 
seed, I have ventured to designate as more truly physiological, al- 
though there is probably in reality no sharp line of demarcation be- 
tween physiological and morphogenetic in problems of the kind under 
consideration here. 
Carnegie Institution of Washington. 
BIBLIOGRAPHY OF PAPERS BY THE AUTHOR CONTAINING INFOR- 
MATION CONCERNING THE SERIES OF BEANS DISCUSSED ABOVE 
19 1 2 a. A First Study of the Influence of the Starvation of the Ascendants upon 
the Characteristics of the Descendants. I. Amer. Nat. 46: 313-343. 
1912; II. Amer. Nat. 46: 656-674. 1912. 
1912 b. On Differential Mortality with Respect to Seed Weight Occurring in Field 
Culture of Phaseolus vulgaris. Amer. Nat. 46: 512-525. 1912. 
1912 c. On the Relationship between the Bilateral Asymmetry of the Unilocular 
Fruit and the Weight of the Seed which it Produces. Science, n. s. 36: 
414-415. 1912. 
