580 PEOP. E. B. POTTLTON : NATUEAL SELECTIOlf 



causes breaks down tte moment it is analysed. The view is 

 a superficial one, and cannot be sustained "when the slightest 

 attempt is made to understand the nature of the phenomena it 

 professes to explain. 



(9) Mimetic Hesemblance and Common Warning Colours more 

 characteristic of the Female than the Male Sex. 



These resemblances are far commoner in females than males, 

 and when the two sexes differ in the closeness with which a 

 likeness to some other form is brought about, it is the female 

 which always attains the greater perfection. Examples of 

 mimetic females with non-mimetic males are extremely abundant, 

 being in fact a high proportion of all the cases which occur ; 

 examples of the converse relationship are very nearly unknown. 

 These general statements hold with common warning colours as 

 well as with truly mimetic species ; they are equally true in all 

 the warmer parts of the world where examples of mimicry are 

 well known and abundant. 



In the numberless cases in which a non-mimetic male is 

 attended by a mimetic female, the former bears the ancestral 

 appearance, so that when m'c pass to a land where both sexes of 

 the representative species are non-mimetic, hoth resemble the 

 non-mimetic male of the former species. In a long series of 

 related species, moreover, the males are found to be nearly alike, 

 while the females diverge in all directions after the species 

 which serve them for models. Furthermore, the females, by 

 reversion, are in rare instances brought back towards the ances- 

 tral type represented by the males. 



It is hardly neceseary to point to examples, for these general 

 principles will probably be at once conceded by any who have 

 made a study of the subject. I may, however, allude to the 

 non-mimetic Papilio meriones of Madagascar and the related 

 forms with similar males but widely different mimetic females 

 on various parts of the mainland of Africa ; to the general 

 resemblance between the males of so many forms of SypoUmnas 

 of the holina group to each other and to those of S. misippus, 

 &c. ; to the varying degrees of reversion towards the appearance 

 of the male presented by occasional females of Hypolimnas 

 holina. 



These relationships are the reverse of those which usually 



