XXXIV 



form with a few metallic dots the normal one, while in my opinion the green 

 is the original form, now rarely met with, and the other the one which has 

 advanced further in the normal darkening process. According to his obser- 

 vations on a great number of pupae, those reared in broad daylight with light- 

 coloured surroundings were of the green form and those in darker surroundings 

 brownish-grey. In the green ones the usual metallic dots were present ; he 

 once found such a chrysalis in the natural state wich was entirely of a golden 

 lustre and on this occasion quotes the opinion of C. Ed. Venus that this 

 should be the result of an intense solar irradiation. The results mentioned, 

 however, only concern the large majority of the pupae, on which he experi- 

 mented ; contrary results occurred also, although in a much smaller number 

 and even when reared in complete darkness the green form occurred occasionally. 



From larvae of Vanessa Cardui L. and V. Urticae L., which pupated in 

 a temperature of 37^ C. against white linen in full daylight, Standfuss obtained 

 pupae of a more or less white general shade but others reared similarly in a 

 temperature of 8^ — 23'' C. assumed the usual brownish- grey hue. 



Prof. Dr. J. VossELER discusses in Zeitschrift fiir Wissenschafilkhe Insekten- 

 biologie. Band Hi, {igo/), p. 204, the pupae of Papilio Demoleus L., reared 

 by him in quantity in East Africa. Although a whole-hearted supporter of the 

 theory of mimicry and speculating on the subject to his heart's content, and 

 like Kathariner and others retaining the likewise antiquated tenet — attributing 

 the origin of the colours in pupae in relation to their environment to chromo- 

 photographic action — his observations on the matter are not devoid of im- 

 portance. He states that the pupae of this species vary from very bright yellow, 

 yellow, green, and bluish-green to bright and dark brown with green dots and 

 invariably marked with the same dark band ; the ventral side is brightest in 

 colour and thus most strongly imitates the colour of the environment; the 

 colours of bark and wood especially are imitated best, yet this imitation is 

 never absolute but is invariably confined within certain limits. 



BoRDAGE also reared some pupae of Papilio Demoleus L. in the Mauritius 

 which, according to him, are grey or yellowish-green, the dorsal side some- 

 times more reddish-brown, while the ventral side is yellowish-green. The colour 

 of the environment where these pupae are formed, such as bark or leaves, 

 appeared to have no influence on the colour of the pupae, neither did light 

 or darkness, sothat under these conditions pupae of both colours occurred. 



With reference to Acraea pupae from South Africa, Mr. Mansel Weale 

 informs us that in his experience a light or dark environment would cause these 

 to be lighter or darker in colour but that otherwise their colour did not change. 



Finally some investigations have been instituted concerning the colour of 



