262 Experiments upon the colour-relation, de. 
pigment; while the other was, at the time of examina- 
tion at Oxford, dead, and so could not be accurately 
described. It appeared, however, as if the black spots 
had been strongly pronounced and accompanied by 
an unusual ‘‘ dusting.” Mr. Griffiths and I had, how- 
ever, examined it whilst it was alive, and the following 
description is given in Mr. Gniffiths’ note-book :— 
“Green ; thorax and wing-cases dark; median yellow 
stripe strongly spotted.” 
C. Here also a conflicting colour experiment was 
attempted, but with only a single larva, which had been 
treated as described above until Stage III., when a strip 
of bright Red opaque paper was added posteriorly. 
Result.—The pupa was dark (3), typical and yellowish. 
The red may have had some influence here, for the 
colour is darker than any produced by green alone 
either in these or in Mr. Poulton’s experiments. On the 
other hand, the increased darkness is not extreme, and 
it is impossible to feel confidence in the results shown 
by a single pupa. 
The results with green harmonise with Mr. Poulton’s 
records. 
VI. Blue. 
A very pale and transparent blue tissue-paper was 
used. i 
Data.—F ive larve, one of which was taken on cabbage 
(and the only one not fed upon mignonette) ; all pupated 
from Aug. 24th to Sept. 7th. 
Results.— 
1 pupa was (2), with a pinkish ground colour; the pupa was very 
black anteriorly and on the wings, but the pink 
ground colour very distinct and light, in patches 
anteriorly, and almost uniform posteriorly : 
hence classed as a (2), though it has the pigment 
of a (1) in parts, with the ground colour of a (3) 
or a (4) elsewhere. A very remarkable pupa. 
3 pupe were (4), 2 typical and pinkish ; 1 typical and yellowish. 
1 pupa was light (4), typical and pinkish. 
5 
As in Mr. Poulton’s experiments (with a much darker 
shade of blue) no special effects seem to have been pro- 
duced by these surroundings. It is, however, probable 
that the extreme paleness of the tint and consequent 
