Vol.. 6, 1920 
GENETICS: D. F. JONES 
67 
either the A or the B plants. If there is a deviation from a perfect pro- 
portion, this will be either in favor of cross-fertilization or self-fertilization. 
Results of Mixed Poi.unations Giving the Total, Number of Seeds, and the 
Numbers in Each Class Forming Proportions, the Deviations of Which 
Expressed as Per cent, from the Closest True Proportions, Are 
Largely in Favor of the Plant's Own Kind of Pollen. P Is 
THE Probability that the Deviations Are Due to the 
Differences of Random Sampling 
POLLEN 
TOTAL 
NUMBER OF SEEDS IN EACH 
CLASS 
DEVIATION 
PROM TRUE 
MIXTURE 
NUMBER 
P 
NUMBER 
OF SEEDS 
A X A 
A X B 
B X A 
B X B 
PROPORTION, 
PER CENT 
1 
3430 
1738 
46 
1602 
4:4: 
+ 0.045 
0 
027 
0.994 
2 
5636 
2133 
145 
3080 
278 
H-0.955 
7 
572 
0.063 
3 
1362 
229 
14 
770 
349 
-1-12.715 
146 
196 
0.000 
4 
3344 
710 
126 
1856 
652 
4-5.465 
61 
203 
0.000 
5 
1956 
589 
6 
1290 
71 
-1-2.105 
28 
718 
0.000 
6 
424 
40 
71 
187 
126 
—11.850 
23 
858 
0.000 
7 
3459 
23 
89 
1507 
1840 
—12.245 
235 
357 
0.000 
8 
7783 
2185 
956 
2619 
2023 
+6.570 
144 
108 
0.000 
9 
8729 
2550 
1288 
2922 
1969 
+3.350 
42 
061 
0.000 
10 
5408 
1084 
1154 
997 
2173 
+8.495 
162 
687 
0.000 
11 
3314 
448 
264 
1505 
1097 
+2.540 
8 
937 
0.030 
12 
3561 
1724 
719 
749 
369 
+ 1.790 
5 
313 
0.053 
13 
736 
185 
391 
95 
65 
—13.625 
55 
051 
0.000 
14 
792 
424 
150 
156 
62 
+ 1.155 
0 
533 
0.894 
15 
3168 
2609 
47 
14 
498 
+47.750 
2889 
561 
0.000 
16 
2224 
723 
8 
74 
1419 
+46.975 
1965 
981 
0.000 
17 
1410 
1303 
3 
4 
100 
+47.960 
1298 
993 
0.000 
18 
1599 
4 
21 
1 
1573 
+7.970 
137 
532 
0.000 
19 
2606 
528 
392 
343 
1343 
+ 18.525 
376 
394 
0.000 
20 
2753 
63694 
897 
77 
1174 
605 
+ 13.050 
283 
002 
0 000 
One great advantage of using endosperm characters in this way is that 
the several kinds of seed develop under nearly as favorable environmental 
conditions as it is possible to obtain, so that selective elimination of zygotes, 
which may favor one class more than another, is reduced to a minimum. 
In those plants in which the cross-fertilized and self-fertilized progeny 
cannot be distinguished until they are grown to maturity there is con- 
siderable likelihood that unequal germination and differential viability 
will tend to favor cross-fertilization. Animals are subject to the same 
objection as material for investigating this problem. 
The method of mixed pollination in reciprocal applications is the simplest 
means of accurately testing the efficiency of two kinds of pollen in compe- 
tition with each other. It is impossible to know definitely the relative 
