342 Professor E. B. Poulton on colour-relation 
in fact one of those on the branch was eating when the 
examination was made. The larve were on the whole 
darkish but very variable. 
M.. Seven larve arranged as in the last set (). One 
larva was dead, 2 were on the branch, and 4 were on the 
muslin. All had left their foot-holds and were healthy 
and irritable. They had evidently eaten. Their appear- 
ance was similar to that of the set last described. 
A complete history of the larve of each set, I to IV, 
subsequent to hybernation, will now be given, followed by 
an account of the careful comparisons of the whole which 
were made from time to time, all the larve being then 
placed on a uniform background of white paper. 
I. THE QUERCIFOLIA LARVZ ON BLACK TWIGS BEFORE 
HYBERNATION. 
A. The 3 chequered black-and-white quercifolia larve on 
black twigs throughout. 
April Tth—Re-fed. Three black larve with small 
white patches. Unchanged when re-fed on the 10th: all 
on twigs. 
April 16th—Re-fed. Two larvee on twigs, 1 on haw- 
thorn: appearance unchanged, as also when re-fed on 20th, 
23rd, 27th, and May 3rd: all larve invariably resting on 
the twigs. 
May 7th—Re-fed. One larva unaltered, while 2 had 
changed skin, and the white markings had become less 
bright. In one of these the old skin was still adherent 
anteriorly, This larva was removed to cylinder C (p. 344). 
The other older darker larva was sent to Lord Walsingham 
-on May 11th. 
May \\th.—Re-fed. The single remaining larva was at 
rest on twig; it was still black with white markings, and 
was unaltered when re-fed on the 17th, 22nd, and 25th, 
its position on the twig being noted on the two former 
dates. It was sent to Lord Walsingham on May 31st. 
B. The five darkest quercifolia larve with lichen-covered 
sticks during and after hybernation. 
April 7th. Re-fed. All 5 larve black, 3 of them with 
white spots. 
