Mimicry 55 
one, which is especially remarkable, and which has been thoroughly 
investigated, Papilio dardanus (merope), a large, beautiful, diurnal 
butterfly which ranges from Abyssinia throughout the whole of Africa 
to the south coast of Cape Colony. 
The males of this form are everywhere almost the same in colour 
and in form of wings, save for a few variations in the sparse black 
markings on the pale yellow ground. But the females occur in 
several quite different forms and colourings, and one of these only, 
the Abyssinian form, is like the male, while the other three or four 
are mimetic, that is to say, they copy a butterfly of quite a different 
family the Danaids, which are among the immune forms. In each 
region the females have thus copied two or three different immune 
species. There is much that is interesting to be said in regard to 
these species, but it would be out of keeping with the general tenor 
of this paper to give details of this very complicated case of poly- 
morphism in P. dardanus. Anyone who is interested in the matter 
will find a full and exact statement of the case in as far as we know 
it, in Poulton’s Essays on Evolution (pp. 373—375!). I need only add 
that three different mimetic female forms have been reared from the 
eggs of a single female in South Africa. The resemblance of these 
forms to their immune models goes so far that even the details of the 
local forms of the models are copied by the mimetic species. 
It remains to be said that in Madagascar a butterfly, Papilio 
mertones, occurs, of which both sexes are very similar in form and 
markings to the non-mimetic male of P. dardanus, so that it probably 
represents the ancestor of this latter species. 
Tn face of such facts as these every attempt at another explana- 
tion must fail. Similarly all the other details of the case fulfil the 
preliminary postulates of selection, and leave no room for any 
other interpretation. That the males do not take on the protective 
colouring is easily explained, because they are in general more 
numerous, and the females are more important for the preservation 
of the species, and must also live longer in order to deposit their 
eggs. We find the same state of things in many other species, and 
in one case (Elymnias undularis) in which the male is also mimeti- 
cally coloured, it copies quite a differently coloured immune species 
from the model followed by the female. This is quite intelligible 
when we consider that if there were too many false immune types, 
the birds would soon discover that there were palatable individuals 
1 Professor Poulton has corrected some wrong descriptions which I had unfortunately 
overlooked in the Plates of my book Vortrége uber Descendenztheorie, and which refer 
to Papilio dardanus (merope). These mistakes are of no importance as far as an under- 
standing of the mimicry-theory is concerned, but I hope shortly to be able to correct 
them in «, later edition. 
> 
