4 Harris, Observations on the Physiology of Seed Development in Stapliylea. 
to attach mucli weight to these constants if he had any regard to 
their probable errors. 
Taking next r ns , we find that eigbteen out of twenty differ 
from zero by less tban. 100, and tbat the two others only slightly 
exceed this limit. 
Of the values for r nf , fourteen fall below our limit of trust- 
worthiness, fiye exceed it by not inore than .063, and a single 
individual, again plant 28, shows a more substantial correlation. 1 ) 
Xotwithstanding the low values of the coefficients with regard 
to their probable errors, there may still be some significance in 
these constants. Suppose the real relationship between the char- 
acters to be 0; we would then not expect to find correlations of 0 
when we calculated the coefficients upon the basis of three hundred 
locules, but results falling above or below this value by an amount 
due to the probable error of random sampling. This is precisely 
the condition observed; some have the positive and some the ne¬ 
gative sign. Xow by comparing the number of cases in which the 
values fall above and below 0, we may be able to get some idea 
of the sign, at least, of the correlation in a population of individuals. 
For r no nine of the coefficients have the positive and eleven 
the negative sign. In a series of only twenty individuals one 
could not expect a more nearly even division. The positive con¬ 
stants average . 1305 while the negative ones give a mean cor¬ 
relation of —.0718. If we omit the high value for plant 28, the 
positive values average . 1022. The mean for the twenty series, 
having regard to signs, is + . 0192. But the Standard deviation 
of the coefficients =.1226, about, and .67449 o r =|/20 = . 0185. 
The mean is, therefore, .0192 + .0185, and we conclude that 
so far as our data go there is no evidence in favor of any re¬ 
lationship between the number of fruits per inflorescence and the 
number of ovules per locule. 
Consider r ns . Of the twenty, four are positive as compared 
with sixteen negative, while if actually r — 0 and the results were 
due to random sampling, we should expect 10 and 10. Observation 
differs from theory by six cases. For the probable error, we 
have . 6745 ]/ 20 x . 5 x. 5 = 1.51, and 6 + 1.51 is perhaps significant. 
The mean of the four positive coefficients is . 0399 and that for 
the sixteen negative —.0598; for the whole twenty individuals 
A = —.03987. By the brüte force method, o r — . 0530 and 
E Ä =. 00799. Xow an average correlation of —-.0399 + . 0080 
may be significant, but with such low values throughout any cautious 
statistician would hesitatc in attaching much significance to them. 
The constants for r nf need not be discussed in detail. Since 
the constants for r no are about equally divided between positive 
and negative while those for r ns are preponderatingly negative, 
*) Naturally the Suggestion of an arithmetical blunder in the case of this 
individual will occur to the reader, but I have been unable to find any elip in 
the work. 
