Séance du 16 Avril 11)24 
143 
The following conclusions have been drawn: — 
1. Virginity lengthens life, but only to a small 
extent; this is not an advantage either to the female 
or to her progeny, when there are descendants. 
2. Out of 5 1 unfertilized females, 3 o % made no 
egg-cases, 55 % made less than 12 and only eight or 
1 5 % made a number — from i 3 to 21 — comparable 
to the number laid by fertilized females. As might 
have been expected, there is in general a reduction in 
the number of egg-cases laid. It is, however, interest¬ 
ing to notice that three independent observers could 
conscientiously advocate three different hypotheses and 
bring forward quite sound evidence to demonstrate 
any one of them, more especially if it so happened 
that no young hatched from the few egg-cases obtained 
by the second. The first would maintain that unfer¬ 
tilized females made no egg-cases, the second that they 
made a few' but that the eggs did not develop and the 
third Would very certainly be accused by both the 
others of being an unsound and unreliable observer. 
Such a quarrel as would ensue would not be the first 
of its kind. 
3 . The cross-section of an egg-case of this species 
is the same throughout the part which contains eggs 
and, except in a few unimportant cases, is the same 
for all. The length of the egg-case may therefore be 
taken as a measure of its size. 
Egg-cases laid by fertilized females are on the 
whole larger than others, but never exceed the length 
