452 
Intra-Class and Inter-Class Correlations 
TABLE II. 
Intra-Ovarial Correlation for Seeds per Locule. 
Seeds of Second Locule. 
o 
CO 
0) 
CD 
-Jl 
0 
1 
2 
3 
4 
5 
6 
7 
8 
Totals 
0 
70 
123 
126 
54 
31 
12 
4 
420 
I 
123 
334 
414 
311 
150 
72 
47 
8 
1 
1460 
2 
126 
414 
714 
642 
447 
204 
102 
23 
4 
2676 
3 
54 
311 
642 
1002 
854 
523 
237 
47 
14 
3684 
k 
31 
150 
447 
854 
1036 
868 
522 
102 
26 
4036 
5 
12 
72 
204 
523 
868 
1010 
752 
179 
52 
3672 
6 
4 
47 
102 
237 
522 
752 
916 
252 
84 
2916 
7 
8 
23 
47 
102 
179 
252 
150 
79 
840 
8 
1 
4 
14 
26 
52 
84 
79 
36 
296 
Totals 
420 
1460 
2676 
3684 
4036 
3672 
2916 
840 
296 
20000 
But the same result can be obtained from the constants for seeds per locule and 
the seriation of total seeds per fruit (Biometrika, Vol. VIII., pp. 60 — 62) in 
precisely the same way as in the preceding illustration without the excessive 
labour of tabling 20000 combinations. 
Suppose, now, we had been given the physical constants only — not the 
distributions — for seeds (or ovules) per locule and total seeds (or ovules) per 
fruit. The correlation is still easily deduced, for the sum of the squares of 
total seeds, = S [S (s')] a for locules, is given by substituting from Biometrika, 
Vol. vni., Table XII, 
S [X {s')Y/N = 2 (.s'/ 2 )/iV = a H - + s t * = (7-0506) 2 + (5 x 3-9056) 3 = 431-05374436, 
where the subscript t indicates total seeds per fruit. Since N = 1000 for fruits, 
aS'[S(s')] 2 = 431053-74. 
In the same manner we get for the individual locules 
% (s'2)/N = af + s 2 = 18-338652, 
or since N for locules =5000, 2 (s' 2 ) = 91693'26. Hence, by (vii), 
r = {(431053-74 - 91693"26)/20000 - (3 9056) 2 }/(l-7564) 2 
= 1-71431264/3084941 = -5557. 
The extent of agreement with other methods depends merely upon the number 
of decimal places retained in the constants. 
The importance of intra-class correlation coefficients in physiological work is 
emphasized by a comparison of this with the preceding, III (Aa) 1, result: 
For ovules per locule, r = '3843 + '0081. 
For seeds per locule, r = "5557 + "0066. 
Excess for seeds, = -1714 + -0104. 
