434 Mr. F. Merrifield on Temperature Hxperiments 
scarlet patches on the under side are only found in six out 
of forty-eight which were subjected to 99° or upwards, and five 
out of the six were so exposed for practically their whole pupal 
period. 
In the opposite direction of low temperature, I tried 
further experiments with V. atalanta, the most marked 
results of which I exhibited at the meeting of the Ento- 
mological Society on the 8th November, 1895. ‘They con- 
firm, and in some cases carry further, the results obtained 
in the previous year. The low temperature causes much 
substitution of white, lavender, or metallic blue-green 
scales (one of these colours seeming readily in this insect 
to pass into another of them) for the black in normal 
specimens ; the large white spot on the costa is greatly 
enlarged and spread, and the tendency of the third of the 
row of submarginal spots to ocellation which is above 
referred to, as caused by a high temperature, is shown in 
a different manner by the low temperature, which tends 
to form a whitish ring round, and very near to it 
(this third spot is on the underside ocellated in normal 
specimens), 
The extreme low temperature forms are, on the 
whole, so decidedly smaller than the average, that I am 
inclined to think the low temperature is a cause of 
reduced size in this species, more especially as those at 
the high temperatures, even where this is so extreme as 
to kill some of them, are all of full size. 
[ Yorced.—Resolution of inner margin of red band fairly 
marked. 
Refrigerated.—Marginal blue much extended, especially 
about anal angle of hindwing and in centres of spots of 
“Series IV.” ; spots of “Series D”’ often ringed with 
pale blue, apart from ocellation; indications present of 
bluish centres to ‘ Series III.” in hindwings; greater 
general blackness. | 
Mr. J. J. Walker has kindly given me a specimen from 
Gibraltar which resembles, in its main features, some of 
my earliest individuals. It was taken, recently emerged, 
on the 17th February, and I find that the mean tem- 
perature of January and February at Gibraltar may be as 
low as 48°7° and 50°9°, Dr. Chapman has kindly sent 
