370 Mr. F. Merrifield and Mr. E. B. Poulton on 



jff.— EXPERIMENTS UPON THE PUP^ OF Vanessidse. 



1. Experiments upon the Pupse, of Vanessa urticse and Pyrameis 



cardiii. (C. B. S. and E. B. P.) 



2. Experiments upon the Pupse of Vanessa io. (Mabel E. 



NoTLEY, Flobence A. Wright and E. B. P.) 

 /.—EXPERIMENTS AND OBSERVATIONS UPON THE 

 SUSCEPTIBILITY OF CERTAIN LEPIDOPTEROUS 

 LARV/E AND PUP^ TO THE COLOURS OF THEIR 

 SURROUNDINGS. (A. H. Hamm and E. B. P.) 

 X— OBSERVATIONS ON THE COLOUR-RELATION BE- 

 TWEEN A COLEOPTEROUS SPECIES {Cleonus snlcirostris) 

 AND ITS SURROUNDINGS. (W. Holland and E. B. P.) 

 L.— APPENDIX. THE QUALITY OF LIGHT REFLECTED 

 FROM THE COLOURED AND OTHER BACK-GROUNDS 

 EMPLOYED IN THE EXPERIMENTS RECORDED IN 

 THE PRESENT MEMOIR. (Sir John Conroy, F.R.S., and 

 E. B. P.) 



^.—INTRODUCTORY. 



In Prof. Poulton's paper in the Philosophical Transactions 

 of 1887, vol. 178 B. pp. 311-441, "An Enquiry into the 

 Cause and Extent of a Special Colour-relation between 

 certain exposed Lepidopterous Pupse and the Surfaces 

 which immediately surround them," he recorded some 

 experiments on the full-fed larvae of Pcqnlio machaon from 

 which he inferred that this species was not susceptible to 

 the colours of its surroundings, a conclusion which sur- 

 prised him, having regard to the marked dimorphism of 

 the pupge [the larva not showing any corresponding dimor- 

 phism to which the different colours of the pupse could be 

 ascribed, as in the case of the geometrid genus Epliyra 

 (Phil. Trans. /. c. p. 437)], and Prof, Poulton suggested tliat 

 further experiments should be tried, more especially as he 

 had had only eleven larvae, of which two died. At the 

 meeting at Cambridge in August last of the International 

 Congress of Zoology M. Bordage of Reunion communicated 

 a paper in which he expressed the opinion that the pupsB 

 of the genus Papilio appeared to have lost any suscepti- 

 bility to colour which they might at one time have 

 possessed, but Mr. Trimen, your President, gave an instance 

 to the contrary, and expressed the opinion that too few 

 experiments had been made to warrant at present any 

 conclusion on the subject. 



