J. W. Jenkinson 
165 
and end of the series. Nor is it due to any peculiarity of the ova or spermatozoa. 
B, C, D and E, it is true, were all obtained from the same female, though not all 
fertilized by the same male ; F and G were also produced by the same parents, 
and so were iV and 0, but in J the distribution is a random one : in / it is very 
strongly gathered about 0°, though in these two cases ova from one female were 
fertilized by spermatozoa from one male. 
(/3) The Plane of Symmetry and the First Furrow (Table XII.). 
In B, G, G, H, I and J the frequency is greatest about 0° ; in i) and K the 
frequency about 90° rather exceeds that about 0°; in ^ the variation is a random 
one. 
TABLE XII. 
Plane of Symmetry and Fii^st Furroiv. 
Frequencies in the Individual Experiments. 
Experi- 
ment 
Frequencies 
B 
4 
2 
4 
2 
4 
1 
6 
12 
3 
3 
3 
1 
5 
C 
3 
1 
4 
2 
2 
3 
3 
5 
12 
2 
1 
2 
1 
3 
3 
D 
6 
1 
1 
1 
4 
1 
2 
1 
6 
E 
3 
2 
6 
4 
2 
2 
3 
4 
5 
5 
2 
3 
3 
7 
4 
4 
3 
3 
G 
1 
1 
2 
1 
1 
8 
4 
1 
1 
3 
3 
H 
2 
3 
1 
1 
3 
5 
3 
17 
14 
2 
5 
2 
2 
3 
K 
5 
6 
2 
3 
2 
2 
2 
5 
3 
8 
5 
3 
3 
3 
4 
1 
3 
11 
J 
2 
2 
3 
1 
3 
10 
5 
1 
3 
3 
1 
2 
2 
3 
2 
I 
1 
1 
3 
4 
3 
1 
1 
1 
1 
90 80 70 60 50 40 30 20 10 o 10 20 30 40 50 60 70 80 90 
+ 
It is clearly impossible to suppose that these differences are due to any pecu- 
liarity in the eggs, or spermatozoa produced by individual parents. 
(7) In the case of the Plane of Symmetry and the Sagittal Plane the tendency 
towards coincidence is shown in every experiment (Table XIII.). 
TABLE XIII. 
Plane of Symmetry and Sagittal Plane. 
Frequencies in the Individual Experiments. 
Experi- 
ment 
Frequencies 
B 
1 
1 
1 
5 
4 
8 
7 
4 
2 
2 
3 
5 
4 
2 
1 
3 
C 
2 
3 
3 
1 
7 
9 
9 
4 
8 
1 
1 
2 
D 
1 
3 
1 
2 
10 
10 
15 
12 
2 
2 
1 
E 
1 
1 
3 
4 
4 
.5 
17 
12 
4 
3 
3 
2 
2 
3 
G 
1 
1 
2 
1 
2 
3 
11 
13 
4 
10 
4 
1 
2 
H 
1 
1 
2 
5 
11 
10 
21 
7 
G 
5 
2 
1 
1 
H' 
1 
1 
3 
6 
8 
7 
3 
1 
K 
1 
1 
2 
1 
1 
3 
5 
5 
15 
9 
11 
1 
3 
3 
2 
2 
1 
1 
J 
1 
3 
4 
6 
4 
2 
6 
3 
1 
1 
I 
1 
1 
1 
1 
4 
3 
1 
1 
2 
90 80 70 60 50 40 30 20 lo o 10 20 30 40 so 60 70 80 
