244 
Biotiomicii of Pediciilus 
TABLE VIII. 
The influence of food supply upon [a) the number of eggs 
laid and (b) their fertility. 
Method. A number of lice in the larval stage were reared until adult. 5 and 5 
wore then placed in each of two boxes. Those in box B were fed at night only, 
period for feeding available about 7 hours. In box A additional feeding time, 
2 or 3 hours, was given by day. Boxes kept in a breast pocket by day. (A false 
start was made owing to a $ in one of the boxes escaping during the counting of the 
eggs; as the escape was not noticed until the 10th day a fresh start was made on the 
11th day with four pairs in each box.) 
Box A. 
Number of eggs laid eacli day. 
Figures at top indicate days in 
the life of the ? 
12 13 14 15 16 17 18 19 
Number of eggs laid 32 25 66 34 35 34 30 
Total 256= a daily average of 8 per $ 
Number of eggs hatching, each 
day’s laying treated as a 
separate batch 
12 13 14 15 16 17 18 19 
30 
23 
62 32 30 30 26 
Total 233 
Percentage hatching =91 %. 
Box B. 
Number of eggs laid each day. 
Figures at top indicate days in 
the life of the ? 
12 13 14 15 16 17 18 19 
Number of eggs laid 28 17 49 30 22 28 27 
Total 201 =a daily average of 6-3 per $ 
Number of eggs hatching, each 
day's laying treated as a 
separate batch 
12 
13 
14 15 16 
17 
18 
19 
28 
17 
49 29 
21 
25 
26 
Total 195 
Percentage hatching = 97 %. 
Reverse order of feeding. 
On the 20th and 21st days the insects in both boxes were treated alike as regards feeding 
(at night only) and no records of egg laying were made. On the 22nd and following 
days the insects were fed in the reverse order; A one period of about 7 hours at night, 
B two periods 7 hours at night and 2 or 3 hours during the day. On the 26tri 
day a $ in box A died and one was also removed from box B. On the 28th day the 
insects in box B were not fed during the day and both boxes were removed from 
pocket during that day. 
Box A. 
Number of eggs laid 
Number of eggs laid each day. 
Figures at top indh ate days in 
the life of the $ 
23 
24 
25 
26 
27 
28 29 
30 
18 
18 
15 
18 
17 
28 
14 
Total 128 = a daily average of 4*5 per ? 
Number of eggs hatching, eacli 
day’s laying treated as a 
separate batch 
23 
24 
25 
26 
27 28 29 
30 
17 
17 
13 
16 
14 28 
12 
Total 117 
Percentage hatching = 91 %. 
Box B. 
Number of eggs laid each day. 
Figures at top indicate days in 
the lire of the ? 
Number of eggs hatcJiing, each 
day's laying treated as a 
separate batch 
23 24 25 26 27 28 29 30 
23 24 25 26 27 28 29 30 ' 
Number of eggs laid 32 3(1 28 25 23 28 21 
3’otal 187 = a daily average of G G per J 
31 30 24 23 20 27 21 
Total 176 
Percentage hatching =94 %, 
