200 
PHIL RAU AND 
NELLIE RAU 
the 52 fertilized and the 28 unfertilized females of 1910 we found!® 
that life was cut short while most of the insects retained many 
eggs. 
Now if the duration of life be an adaptation for the good 
of the species, why were not such lives permitted to continue? 
In many cases also a lapse of time, sufficient for completing ovi- 
position, intervened between the last egg-laying and death. 
Tables 17 and 18 shows the number of eggs each female retained 
and the number of hours it lived after ceasing to oviposit.?° 
Fertilized females 
TABLE 17 
EGGS HOURS EGGS HOURS EGGS HOURS | EGGS HOURS 
240 0 41 16 12 14 3 0 
165 8 Aen 7 10 0 | 3 30 
151 0 34 | 0 9 40 2 0 
119 15 31 14 9 ? 1 7 
105 7 29 14 8 OF 1 15 
101 16 27 6 8 384 1 14 
95 38 22 7 8 ii | 0 96 
94 6 20 0 7 ? 0 15 
93 60 20 | 0 6 ? 0 4 
80 17 18 15 5 41 0 39 
72 0 15 7 5 0 0 8 
56 12 14 38 5 12 0 38 
54 o | is 15 3 24 0 ? 
TABLE 18 
Unfertilized females 
EGGS HOURS | EGGS HOURS | EGGS HOURS 
270 ? 103 | 14 40 2 
257 14 102 ? 37 0 
247 ? |. 100 ? 32 24 
189 12 | 85 6 31 30 
179 0 | 80 0 | 23 ? 
144 ii | 68 0 | 21 0 
137 6 | 62 2 17 ? 
135 eo iniaeas 0 2 ? 
133 10 | 48 36 2 ? 
110 ? | 
19 Trans. Acad. Sci., St. Louis, vol. 20, p. 314-315, 1911. 
20 Less than six hours is designated by 0. 
