J. A. Harris 
463 
TABLE XIII. 
Correlation for Ovules and Seeds per Locule in Hibiscus. 
Seeds per Locule. 
O 
0 
1 
2 
1 
3 
4 
5 
6 
7 
8 
Totals 
2 
1 
3 
o 
3 
2 
5 
4 
4 
8 
28 
17 
6 
63 
5 
6 
47 
76 
109 
86 
41 
365 
6 
49 
169 
315 
490 
573 
525 
355 
2476 
7 
30 
97 
167 
221 
237 
244 
235 
103 
1334 
S 
14 
40 
81 
84 
107 
108 
139 
107 
74 
754 
Totals 
105 
365 
669 
921 
1009 
918 
729 
210 
74 
5000 
Comparing other constants for Hibiscus : — 
Direct Intra-class for Ovules, r = -3843 + 0081, 
Direct Intra-class for Seeds, r = "5.557 ± "0066, 
Cross Intra-class for Ovules and Seeds, r = "1320 + - 0093, 
Organic for Ovules and Seeds, r = "2722 ± -0088. 
In all cases the probable error is calculated on the basis of the actual, not the 
weighted number of locules. 
Illustration {III — -Bit) 9. Gross Homotypic Correlation for Number of Ovules 
and Number of Seeds per Pod in Robinia. 
From Tables VI, VII, and VIII supra, we deduce 8 [S (o) 2 (*')] = 1907053G 
which taken in conjunction with S (oV) ='8 [X (o's 1 )] = 141476 taken from the 
organic correlation table for ovules and seeds in Biometrika (Vol. VI. pp. 441 — 442) 
and the physical constants o, s, a 0 , a s , given under illustration (III — Ab) 5, gives 
= {{8 [X (o') 2 (*')] - S [S (o's')]}/S [n (v - 1)] - os}/<r 0 <r s = "383. 
This may be compared with ?•„„, = - 452 and r Sl s 2 = "449. The discussion of the 
biological significance of the results from this and the preceding illustration must 
be reserved. 
Problem IV. To Determine Direct or Cross Inter-Class Correlations from the 
First Two Moments of the Individual Classes. 
Let x be the measure of a character in an individual of one class of p members 
and y be the measure of the same or a different character in an individual of 
another class of q members associated with the first for some logical (e.g., 
biological, or sociological) reason. The coefficient calculated from a table in 
which every x of a first class is compared with every y in the second (associated) 
class may be designated as an inter-class coefficient of correlation. 
The number of entries in an inter-class correlation surface will be S(pq), where 
S indicates a summation of classes. X(x')/p, X(x'-)/p, %(y')/q, %(y'' 2 )/q are the 
59—2 
