158 president's address. 
number of individuals. This is known after the author of 
the hypothesis as Mullerian mimicry. 
In Butterflies, mimicry is sometimes confined to one sex, 
in which case it is almost always the female which mimics. 
As an example of this, I would cite Hypolimnas misippus , 
a species found all over India and Africa, and which has 
recently made its way across to South America. 
The male is of a velvety black colour, with large white 
spots on the wings more or less margined with blue. The 
female, on the other hand, is entirely different both in shape 
and colour. It is of a bright tawny hue, and presents at 
least three different forms. In one form there is an oblique 
bar of white spots across the fore-wing near the apex. In 
a second form this bar is quite wanting, and in the third form 
the lower wings near the base are of a whitish colour. Now 
these three female forms are mimics of a very common 
Butterfly, Danais chrysippus, which also occurs in three 
forms, and which is found wherever H. misippus is found, 
except in America, where H. misippus is rare, and is 
believed to be a recent immigrant. Danais chrysippus is 
undoubtedly a protected insect, and is distasteful to animals 
which feed on Butterflies. Hypolimnas, on the other 
hand, is believed to be good to eat from the point of view 
taken by those creatures which feed on Butterflies. In 
Africa and the drier parts of Western India two varieties 
of D. chrysippus occur, known under the names of dorippus 
and alcippus, and all these three forms are mimicked by 
the female of H. misippus. This example of mimicry would, 
I suppose, be regarded as one to be explained by Mr. Bates’ 
hypothesis. Personally, I think we require more information 
and careful observation before either of these hypotheses 
can be unreservedly accepted. 
I cannot say that I have ever seen any of our British 
Butterflies attacked by birds, except on one occasion a few 
years since, when I saw a Robin in my own garden deliberately 
