134 
GENETICS: T. ELLINGER 
Proc. N. A. S. 
etometer. The following table gives the essential data for the interval 
of 6 years, 9 months and 6 days with the increment from leap years : 
NO. 
L 
cm. 
DIAM. 
INSIDE 
cm. 
AREA 
cm 2 . 
DATE 
INTERVAL 
t X 108 
SEC. 
h 
cm. 
«4 
1012 K 
I 
20.0 
0.55 
0.24 
f 1914- 3-20 
1 1920-12-26 
2.14 
■ 
' 10.12 
9.89 
1.07 
1.10 
II 
15.7 
0.82 
0.53 
J 1914- 3-20 
\ 1920-12-26 
2.14 
7.59 
K 7.22 
1.73 
1.87 
The two values of k found are of the same order, but the one for tube II 
is definitely larger than the one for tube I. This may be due to infinites- 
imal difference in the separated gases (a,a') of the tubes. But since the 
tube II has a shorter (L) and wider column, and a meniscus nearer the 
bend, it is more probable that thermal correction is the cause of the differ- 
ence; for the inside sectional area of II is about 2.2 times larger than that 
of I. The data obtained for k with a cylindrical cartesian diver (Carnegie 
Publications, No. 186, Washington, 1913, p. 21) about 3 cm. in diameter 
of 7.05 cm 2 , in area, are enormously larger than the above, reading a = 
90 X 10 ~ 12 . The result is in keeping with the enormously larger area 
and consequent effectiveness of the solution-temperature mechanism 
which I have described in the preceding paper. 2 Whether in case of 
tube I, a condition of true diffusion has been reached will have to be as- 
certained in the lapse of further years. Meanwhile the question whether 
a long slender cartesian diver may not obviate the discrepancies hitherto 
encountered is worth consideration. 
1 Advance note from a Report to the Carnegie Institution, Washington, D. C. 
2 These Proceedings, 6, 1920 (495-8). 
THE INFLUENCE OF AGE ON FERTILITY IN SWINE 1 
By Tagk Elungkr 
Copenhagen, Denmark 
Communicated by R. Pearl, March 10, 1921 
In the breeding of domestic animals the problem of fertility is of prime 
importance. The neglect of this essential factor has again and again 
caused breeders disappointments and often heavy economic losses. Thus 
it is desirable to study this chapter of the physiology of reproduction 
thoroughly and to examine the factors, internal and external, that affect 
the ability to produce offspring. 
During an investigation on these subjects, in this laboratory the re- 
sults of which are soon to be published, the writer has been confronted 
