J. W. Jenkinson 183 
TABLE XXXIII. 
Correlations. 
Sperm-eutrance 
and 
First Furrow 
Sperm-eutrance 
and Plane 
of Symmetry 
Sperm-sphere 
and Plane 
of Symmetry 
Sperm-path 
and Plane 
of Symmetry 
All cases I 
II 
Towards and in or I 
parallel to furrow II 
Towards furrow only I 
II 
•613 + -038 
•435 ± -074 
•502+ -135 
•006 + -061 
•302 + ^083 
•411fl48 
- -048 + •oei 
•188 ±-088 
•030 + ^06 1 
•479 ±^070 
•725 + ^064 
■086 + -094 
•880 + -040 
I = Eggs close. Axes horizontal. 11 = Eggs spaced. Axes vertical. 
The Plane of Symmetry is, however, affected by gravity, and since gravity and 
pressure are here acting at right angles to one another, there is a marked tendency 
for the Plane of Symmetry to lie at 90' as well as to coincide with the Furrow. 
This of course accounts for the high frequencies in the positive corners of Table 
XXIX. h and the high value of p. 
(3) The Sperm-entrance Meridian and the Plane of Symmetry. 
When the eggs are close and the axes horizontal tlie standard deviation is 
high, 0- = 41-01° + 1-79 (Table XXVI. c), the correlation negligible p = mQ ± '061 
(Table XXIX. c). 
We know that gravity affects the position of the Plane of Symmetry. We 
should expect therefore, that the relation between the Sperm- entrance and this 
plane would be closer if the influence of gravity were removed. This is, as a 
matter of fact, the case; the standard deviation sinks to 25'67° + 1'65, while the 
correlation coefficient rises to -302 + -083 (Tables XXVII. c, XXX. c). 
(4) The Sperm-sphere Meridian and the First Furrow (Table XXVIII. 
I. h, II. h). 
I give the values of the standard deviations since they may have some signifi- 
cance, though I think this is doubtful. It will be seen that in each series 
(I. and II.) they are greater than is the case with the Sperm-entrance Meridian and 
the First Furrow. Nor is the reason for this far to seek. The Sperm-path is 
often parallel to the First Furrow. In such cases the angle between the furrow 
and the meridian including the inner end of the path must needs be greater than 
that between the furrow and the meridian of the outer end of the path, or entrance 
point. 
(5) The Sperm-sphere Meridian and the Plane of Symmetry. 
In view of the known deviation, in many cases, of the First Furrow from the 
Plane of Symmetry, there might possibly be some significant relation between the 
latter and the Sperm-sphere. 
