LEPIDOPTEROUS PUPH1 AND THEIR SURROUNDING SURFACES. 
315 
of the Chamseleon, or may be “ a sun-picture or photograph ” ; and in support of the 
latter view (which has been commonly accepted up to the present date) the writer 
calls attention to the transparent surface of the freshly-formed pupa, which might be 
sensitive to light. In my experiments, described below, I did not meet with any 
parti-coloured pupae, and it is to be noted that a difference between the colours of the 
dorsal and ventral surfaces is common in pupae. It would be satisfactory to expose 
this highly sensitive insect to conflicting colours arranged antero-posteriorly instead 
of dorso-ventrally. Although Mrs. Barber’s figure certainly supports the conclusion 
that the different pupal surfaces may be influenced independently, the conclusion is 
too important to rest on a single instance, and it is to be much hoped that the subject 
will be re-investigated. In the discussion which followed Mrs. Barber’s paper 
(‘ Entom. Soc. Proc.,’ 1874, p. xxiv.), Professor Meldola remarked that “the action 
of light upon the sensitive skin of a pupa had no analogy with its action on any 
known photographic chemical. No known substance retained permanently the colour 
reflected on it by adjacent objects.” 
Mr. J. P. Mansel Weale makes a further interesting addition to the history of 
the subject in his record of experiments upon the larvae of Acrcect esebria (see £ Entom. 
Soc. Trans.,’ 1877, p. 271), also in South Africa. He says : ‘‘Some larvae I confined 
in a dark box, and found that the coloration of the pupae (usually white, with thin 
black and orange markings) was materially altered and darkened, so as closely to 
resemble those of Acrcea liorta, but the individuals were as varied in colour as those 
raised under ordinary daylight. This darkening of colour I have found to be very 
common under the same circumstances in pupae belonging to different families of 
Butterflies. Both larvae and pupae of those Acraeas known to me are found in 
conspicuous places without any attempt at concealment.” 
Mr. J. P. Mansel Weale also records, on p. 275 of the same paper, some 
interesting experiments upon the variable pupae of Callosune keiskamma and those 
of Eroriia cleoclora. He says : “ With reference to the changes in the colour of pupae, 
I believe a very wide field of research is open, and with the improved modes of 
microscopical examination under the spectroscope important revelations on the subject 
of variation will be discovered. I here give the results of some very rude exper im ents 
on this subject. Most of the specimens were reared in glass test-tubes exposed on 
coloured cards, in which they were partially enveloped. They were constantly 
supplied with as little food as possible, in order that their full exposure to the colour 
should not be interfered with. 
“ Pupae of G. keisJcamma. 
(1.) On dead leaves away from light. 
(2.) On stem and on vermilion cards . 
(3.) On vermilion card. 
(4.) Exposed on bush in nature and on yellow gamboge cards 
(5.) On glass tumbler. 
(6.) On green (cobalt and gamboge). 
(7.) On cobalt-blue. 
Dark brown. 
Pale ochreous. 
Pale bluish-green. 
Bright green. 
Pale yellowish-green. 
Ochreous. 
Greenish-w'hite. 
2 S 2 
