Rau—Longevity in Saturniid Moths. 61 
to 15 hours, gave a total of 817 eggs, Be of which were 
infertile. 
SAMIA CALIFORNICA, 
For the Samia californica we have notes on only 2 in- 
sects. (See Table 34.) 
The first mated 28 hours and yielded 20% of infertile 
eggs, while the second, after only a 13-hour mating had 
barely 1% of infertile eggs. 
THE MINIMUM DURATION OF MATING IN RELATION TO 
FERTILITY. 
In our four Cecropia tables already presented are 6 
females which mated only 2 hours, yet had a perfectly 
normal proportion of fertile eggs, while the seventh was 
entirely infertile. We were eager to find just what the 
minimum duration of copulation could be to insure the 
fertility of a normal amount of eggs. 
The period of mating of 3 females was limited to 1 
hour, and of 1 female, to 2 hours; from all these, not one 
egg was fertile. 
Hence the minimum duration of mating required for 
complete fertilization of the egg mass must be between 
1 and 2 hours. Of course the one insect which mated for 
2 hours and yet gave no evidence of fertilization may 
have been sterile, since we have data on a number of 
2-hour matings, recorded elsewhere, a large proportion 
of which proved quite fertile. 
Prriop or [ycusaTIon. 
SAMIA CECROPIA. 
In a previous series of observations on the period of 
incubation of Crecopia eggs,’® we found the period of 
incubation for the eggs deposited each day by each female 
to vary from 6 to 11 days. The length of time for the 
great majority was 8 or 9 days. All but two of the 36 
16 Psyche. 19: 69, 1912. 
