130 Bulletin de la Société Royale Entomologique d'Egypte 
During lite same period the averages between suc- 
cessive ovipasitions of fertilized females varied from 
4.3 to 5.5 days. The averages given in table X are the 
shortest for unfertilized females and reach lip to :>3 
days in the ease of N° 71 which made 5 egg-cases 
and 44 days for N° n 3 which made only two. 
It is therefore quite clear that virginity lengthens 
the intervals between successive ovipositions to the 
extent of about two days at the optimum period of 
the year in the case of the most vigorous females, and 
that this amount may be very greatly exceeded in the 
case of weaker females. 
It should be noticed that, though irregularities 
occur here as well as in the case of the fertilized fe¬ 
males, they are not so great and that they do not com¬ 
pensate one another immediately. Irregularities of 
greater extent without any signs of compensation 
occur in cases of less vigorous females. 
We may therefore conclude that ovipositions 
should follow one another at fairly regular intervals 
during the summer months until the end of the 
laying period and that the period is lengthened by 
virginity in the best cases and in the worst may be 
completely irregular. 
6. The Number of Young which hatch out. 
From table II we see that the number of young 
which hatched from egg-cases laid by fertilized fe¬ 
males was from 862 to 1216. 
From table X we see that no virgin had more 
