434 ME. E. B. POULTON ON THE COLOUR-RELATION BETWEEN EXPOSED 
Series 3.—Transference Experiments. 
A few transference experiments were made with the larvae of these two species, and, 
although on a far smaller scale than with V. urticce, the results prove quite conclusively 
(1) that the larva and not the pupa is sensitive to the colour of surrounding surfaces ; 
(2) that there is some susceptibility to such influences during Stage III. 
I. Gilt , black, and white during Stage III .—September 11. On this date seven larvae 
of those described above in the two cylinders (see Series 2, IV.) were girdled on the 
glass sides, and small pieces of black, white, and gilt paper were glued under each to 
test the effect of these backgrounds during the remainder of Stage III. Two pieces 
of paper were placed under each in such a manner that the method of suspension was 
not interfered with, and yet a complete background was obtained. The experiment 
was conducted as follows :— 
Sept. 11, 9.30 p.m. 
to 9.50 p.m. 
Sept. 12, 8.30 a.m. 
12, 9.50 a.m. 
„ 12, 7.30 p.m. 
12, 9.45 p.m. 
13, 8.40 a.m. 
Gilt paper fixed 
nnder 2 larvae 
Botli pupated . 
Results : Botli (4) ; 
1 pinkish and 1 
greenish ; very 
little pigment 
White paper fixed 
under 3 larva} 
1 pupated 
Results: A (4), pale 
pinkish; a good 
deal of pigment 
for this stage 
1 has pupated ; 
perhaps about 18 
hours of Stage III. 
on the whitepaper. 
Results: (4), pale 
pinkish ; very 
iittle pigment. 
No further change. 
The last larva has 
pupated ; at least 
24 hours on the 
white paper, and 
probably 30 hours. 
Results : (4), pink¬ 
ish ; normal pig¬ 
ment. 
Black paper fixed 
under 2 larvae 
1 pupated 
Results : A (4), 
yellowish - green; 
very little pig - - 
ment 
1 pupated ; hence 
12 hours of Stage 
III. spent on the 
black. 
Results : (4), yel¬ 
lowish-green with 
normal pigment. 
Larva girdled on 
stem of migno¬ 
nette, pinned 
against gilt back- 
ground. 
Pupated. 
Results: A (2) or 
(3) then com¬ 
bined ; yellowish- 
green. 
The pupae were compared with those above, September 15. 
In these pupae there is no evidence that any effect was produced by the back¬ 
grounds during Stage III., or part of it. The results should be compared with those 
of Series 2, IV., which show the colours of the pupae which had not been subjected to 
transference. 
