No. 591] NOTES AND LITERATURE 



185 



On the whole it seems at present doubtful whether any relation of a 

 mimetic nature exists between P. philenor and these three species of 

 Papilio. 



The blue female of the southern f ritillary, Argynnis diana, and 

 our "red-spotted purple," Limenitis (Basilar chia) astyanax, 

 which Professor Poulton has conceived also to be mimics of P . 

 philenor, are likewise regarded as ' 1 very problematically mimetic. 

 The striking resemblance of our "viceroy," L. (B.) archippus, 

 for the "monarch," Banais (Anosia) plexippus, is mentioned, 

 though no allusion is made to Abbott's biometrical study of 87 

 specimens of the supposed ancestral type, L. (B.) arthemis, from 

 which the mimic, archippus, is thought to have arisen. Abbott * 

 by the way, found that the color markings involved in the Poul- 

 ton hypothesis of gradual change by natural selection (e. g., 

 reddish spots) are much less variable than the blues and other 

 colors not considered in that theory, the color pattern of arthemis 

 showing no tendency to break up or to shift in the direction of 

 the Anosia type. 



Punnett next examines critically "Wallace's well-known laws 

 or conditions of mimicry, discusses the evolution of a Ceylonese 

 "mimicry ring" (a group of five superficially similar butter- 

 flies), describes the case of Papilio polytes, the trimorphic 

 "mimetic" and "non-mimetic" females of which are geneti- 

 cally separated from one another by two Mendelian factors, con- 

 siders the enemies of butterflies, and, finally, the relation of 

 seasonal and local variation to mimicry. He arrives at the gen- 

 eral conclusion that there are two prominent difficulties in "ac- 

 cepting the mimicry theory as an explanation of the remarkable 

 resemblances which are often found between butterflies belong- 

 ing to distinct groups," viz., "the difficulty of finding the agent 

 that shall exercise the appropriate powers of discrimination, 

 and the difficulty of fitting in the theoretical process involving 

 the incessant accumulations of minute variations with what is at 

 present known of the facts of heredity. ' ' 3 In view of these diffi- 

 culties, taking his cue from genetics, he suggests that 



Each group of Lepidoptera contains, spread out among its various 

 members, a number of hereditary factors for the determination of color 

 Pattern. . . . Some factors may be common to two or more groups, in 

 which case some of the permutations of the factors would be similar in 

 the groups and would result in identical or nearly identical pattern. 4 



* Washington Univ. Studies, Pt. 1, No. 2, 1914. 



3 P. 139. 



*Pp. 145, 146. 



