Appendix. 131 



following spring. Now under ordinary circumstances 

 all the butterflies which emerged the same season would 

 have been of the Marcellus form, so that the cold changed 

 a large part of these into the form Telamonides, some 

 (probably from those pupae which experienced the lowest 

 temperature) being completely changed, and others 

 (from those pupae which were only imperfectly subjected 

 to the cold) being intermediate, i. e.> only partly changed. 

 It appears also that several pupae experienced sufficient 

 cold to retard their emergence and stunt their growth, 

 but not enough to change their form, these being the 13 

 recorded specimens of Marcellus. Had the degree of 

 cold been equal and constant, the reversion would pro- 

 bably have been more complete. The application of 

 cold produced great confusion in the duration of the 

 pupal period, the emergence, instead of taking place 

 fourteen days after the withdrawal of the cold, as might 

 have been expected from Dr. Weismann's corresponding 

 experiment whhPteris Napi (Appendix I. Exps. 13 and 

 14), having been extended over more than two months. 

 From the results of this experiment it must be con- 

 cluded that Telamonides is the primary form of the 

 species. 



ADDITIONAL EXPERIMENTS WITH PAPILIO AJAX. 



{Communicated by Mr. W. H. EDWARDS, November i%th, 1879.] 



EXP. I. In 1877 chrysalides of P. Ajax and Grapta 

 Interrogationis (the eggs laid by females of the form 

 Fabricii) were experimented upon ; but the results were not 

 satisfactory, for the reason that the author having been 

 absent from home most of the time while the pupae were 

 in the ice-box, on his return found the temperature above 

 5 6 R. And so far as could be told, the ice had been 

 put in irregularly, and there might have been intervals 

 during which no ice at all was in the box. Six chry- 



K 2 



