G. H. F. Nuttall 
21 o 
green 
10 
(7<J, 3?) 
l 
• • 
4 
• 
5 
O 
orange 
8 
1 
• ••• 
4 
• • 
2 
• 
1 
o 
black 
12 
O* 
Ox 
40 
-Kp 
4 
• ••• 
5 
• •• 
1 
• • 
9 
The adults that emerged on green (especially) and on orange, were paler 
than the rest with few exceptions. Those on violet, indigo and blue would 
appear to have become progressively darker the longer they sojourned in 
their boxes prior to moulting. On the other hand the previous sojourn in the 
soiled stock box appears to have exerted an after effect on the insects kept 
on orange, if we compare the results with those of the following experiment. 
To exclude any possible after effects of a previous sojourn on a background 
which would induce darkening, the following experiment was carried out. 
Experiment XII (different colours). 
Lots of 10 first stage larvae, the progeny of pale parents in a clean white 
box, were put in coloured boxes (tabulated below) on 23. ix. 18. On blue, 
violet and black, the first adults emerged on 3. x., and the last on 5. x. On 
green, indigo, yellow and orange, the first adults emerged on 4. x. and the 
last on 6. x., consequently there was no distinct difference in the rate of 
development. 
Colour 
of box 
Pigmentation in 
adult lice raised 
violet 
8 
(6 c?, 2$) 
7 
• ••• 
1 
• •• 
indigo 
r? 
i 
(5 c?, 2$) 
4 
• ••• 
3 
• •• 
blue 
8' 
(7 c?, 1$) 
5 
• ••• 
2 
• •• 
1 
O 
green 
8 
1 
• 
7 
o 
yellow 
10 
(6<?,4$) 
10 
o 
orange 
10 
(4 c?, 6$) 
2 
8 
• •• 
o 
red 
10 
(8 c?, 2$) 
10 
• ••• 
black 
7 (7<?) 
9 
• ••• 
1 
O (killed young) 
This shows more distinctly than Expt. X that lice raised on green, yellow, 
and orange do not become pigmented like the others. 
