120 Bulletin de la Société Royale Entomologique d'Egypte 
TABLE V. 
Giving the percentages of « a », fertilized, and « b » 
unfertilized, egg-cases which fall within the different length 
groups. 
Number 
Length in 
millimetres 
of Cases 
5-10 
10-15 
15-20 
20-25 
25-30 
37 
a 
66 
6 
32 
56 
6 
. b 
202 
23 
48.5 
13 
9 
6 
0.5 
These two tables show very clearly that the egg- 
cases laid by fertilized! females are on the whole 
larger than those laid by others, but on the other hand 
that very large egg-cases are made only by unfer¬ 
tilized females. We shall consider this question in 
the next two sections of this paper. 
4. The Period before Egg-iaying begins. 
It is unfortunately impossible to publish in full, 
in this paper, the details on which the discussion of 
this and of many of the later portions is based. Some 
of the more important dates concerning 24 out of the 
4 o females which made one or more egg-cases may, 
however, be found in table I and table II. 
N os 33 and 119, which laid 8 egg-cases each be¬ 
fore pairing, are included here among the unfertilized 
females. 
All the females became adult during July 1916, 
