( cxvi ) 



the Pseudacraeas with especial intent to prove their con- 

 specificity by the intermediate forms." 



Prof. PouLTON explained that the cable with the word 

 "terra" reached him on Aug. 19, nine days after the Congress 

 had come to an end, and that he had published the discovery 

 in a letter to " Nature " (Sept. 12, 1912, p. 36). The specimen 

 itself had since arrived and was exhibited to the meeting, 

 together with all the other bred specimens referred to in the 

 paper, including the pai^ents of families B, C and D. The 

 pupal cases of the bred Pseudacraeae were also exhibited 

 beside the butterflies which had emerged from them, and, for 

 comparison, there was included a series of the pupal cases of 

 Pseudacraea imitator, Trim., from Natal, presented to the 

 Hope Collection by the late Mr. A. D. Millar, of Durban. It 

 was seen that the two flat dorsal processes were rather less 

 pronounced and the cephalic processes distinctly shorter in 

 the pupae of the Natal form. Comparing Dr. Carpenter's 

 pupae with the whole series of 31 Natal specimens, it was 

 also seen that the apices of the two dorsal pi'ocesses of the 

 Uganda pupae tended to be directed backwards more strongly, 

 and that the contour of the processes and of the segments 

 between them formed a festooned outline instead of one that 

 was nearly smooth. The cephalic processes of the Uganda 

 pupae tended to turn upwards (viz. dorsally) at the tip, those 

 of imitator downwards, while the two processes of the latter 

 were more frequently separated. The Uganda pupae showed 

 the darker pigmentation, but this effect was probably due to 

 conditions. It was highly probable that this procryptic pupa 

 is susceptible to the colours and degrees of illumination of its 

 normal environment. The method of suspension from the 

 edge, near the leaf-tip or near some angle of a partially eaten 

 leaf, was similar in both forms. 



It was not necessary to assume that differences of the kind 

 described above imply specific distinction. Dr. Carpenter's 

 description of the way in which the hollow cephalic and dorsal 

 processes gained their shape in the fresh pupa was an indica- 

 tion that they were of no morphological significance but 

 merely an adaptation which promoted the concealment of the 

 pupa by making it more leaf-like. 



