Gr. H. F. Nutt all 
129 
a day were only laid once, and that 7, 6, 5, 4, 3, 2, 1, and 0 eggs daily 
were laid respectively on 3, 5, 20, 18, 16, 11, 11, and 13 occasions. The 
observation, though incomplete, since it does not cover the whole 
oviposition period, shows the combined influence of limited nutrition 
and moderate temperature on the number of eggs laid. 
II. Capitis. 
Our information regarding head-lice is slight in respect to the 
number of eggs they lay. Railliet (1895, p. 825) states that a female 
laid about 50 eggs in 6 days (an average of 8-3 per day). Harding 
(1898, p. 95), Eysell (1913, p. 47) and other authors give the total 
at 50-60. No observations are recorded of the total number of eggs 
a female may lay under natural conditions. 
Bacot (ii. 1917, pp. 246-248) kept the records of 20 maintained 
by him under conditions similar to clothes-lice but for the addition 
of hair in the boxes; of 20 ?$, 8 laid between 101 and 138 eggs, the 
others less; the daily average was 3-7. In one instance a maximum 
total of 141 eggs was attained. 
The number of eggs laid by head-lice under the foregoing experi¬ 
mental conditions is less than in the case of clothes-lice; but this 
affords no proof that they are less fertile. 
The Number of Eggs laid by Corporis under Natural Conditions. 
Daily Average and Total. 
In the following experiment, 2 dd and 2 ??, on the day of their 
emergence from the third larval stage, were confined in a thick felt 
cell bandaged to my Laboratory Assistant’s arm as described on p. 105. 
The lice were the offspring of adults similarly confined upon the arm, 
and raised in the cell from the egg to the adult stage. Throughout 
the experiment, the insects were only disturbed for a few minutes each 
day so as to permit of an inspection and count of the number of eggs or 
moults and a periodic removal of cast skins and filth. 
The adults moulted on 17. n. 1916, Day 1 of the following protocol: 
Day. 
. 1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
15 
$ A laid .. 
• >4 
2 
10 
11 
12 
11 
12 
9 
11 
10 
10 
10 
9 
8 
11 
? B laid .. 
. 0 
3 
11 
11 
11 
10 
11 
9 
12 
9 
11 
10 
9 
8 
11 
Day. 
. 16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
5 A laid .. 
. 8 
11 
10 
10 
10 
8 
9 
1 
9 B laid .. 
. 9 
11 
9 
11 
10 
9 
9 
12 
12 
11 
11 
9 
8 
5 
Parasitology x 9 
