300 THE JOURNAL OF PHILOSOPHY 



than A. dominicanus, were encouraged by natural selection, and 

 under its guiding hand the form mima eventually arose from wahl- 

 bergi. 



"According to Mendelian views, on the other hand, A. echeria 

 arose suddenly from A. dominicanus (or vice versa), and similarly 

 mima arose suddenly from wahlbergi (p. 134). ... On this view 

 the genera Amauris and Euralia contain a similar set of pattern fac- 

 tors, and the conditions, whatever they may be, which bring about 

 mutation in the former lead to the production of a similar mutation 

 in the latter" (p. 135). 



Although Professor Punnett ought to be competent to express 

 "Mendelian views," I am pretty confident that he will be unable to 

 find a single Mendelian writer who would accept his assumption 

 about the origin of the two species of Amauris. But, however this 

 may be, it is quite certain that no Darwinian, modern or ancient, and 

 certainly no student of insect systematics, has committed himself 

 to the belief that one of these two Danaine models has directly 

 arisen from the other. 



The late Dr. F. Moore, in his revision of the Danaincef placed 

 echeria and dominicanus in separate genera. In this he was prob- 

 ably wrong, but they are certainly widely separated. Amauris 

 niavius niavius of the west, together with the eastern sub-species, 

 niavius dominicanus, occupies an isolated position in the genus 

 Amauris, and it is absurd — I can use no milder word — to suggest 

 that echeria arose directly from either of them. Hence, the whole of 

 Professor Punnett 's assumption of a parallelism in origin between 

 model and mimic, which Mr. Sumner finds so comforting, falls to 

 the ground. 



May I say in conclusion that, although the relationship between 

 the two mimetic forms of Euralia is undoubtedly Mendelian, I can 

 not believe that one of them arose suddenly from the other? I be- 

 lieve that any one who looks at Professor Punnett 's Plate VI. will 

 hesitate to accept the view that the details of either of the two 

 mimetic patterns — reproducing with great precision the pattern of 

 a species belonging to a different sub-family — arose all at once from 

 the other by mutation. 



I have, furthermore, some evidence in support of the conclusion 

 that the origin of the mimicry was gradual. Another closely related 

 species, Euralia dinarcha, presents on the west coast of Africa two 

 forms very roughly resembling the Danaine models which are so won- 



«Proc. Zool. Soc. London, 1883, page 201. Dr. Moore placed echeria and 

 an allied species in Nebroda. Aurivillius in his great ' ' Rhopalocera JEthiopica ' ' 

 places niavius, including the eastern form dominicanus, second and echeria 

 fifteenth in the genus Amauris. 



