MIMICRY IN EAST AFRICAN BUTTERFLIES 91 
nearly so easy to catch as one would be led to expect from 
their appearance. 
This brings me to the end of the large combinations centred 
round the different species of Danaidae found in the country, 
but there are yet two species of this subfamily to be found in 
our area, and both of these are objects of mimicry. The first of 
these is the beautiful Melinda formosa , which is a somewhat 
local species of a limited range. It may be described as a black 
insect with nearly half the fore wings near the base orange 
brown, and with numerous rather large pale blue -green spots 
over the rest of the wings, the basal area of the hind v T ings 
being occupied by a large blotch of the same colour divided 
into three parts by the black nervures. This is very accurately 
imitated by the rare and fine Papilio rex, though it may be 
separated from it immediately by the important structural 
differences. (The Papilios have S’x perfect legs whilst all the 
Danaines have the first pair aborted.) The other Danaine 
is Tirumala linniace. This species does not differ sufficiently 
from the Indian representative to be considered as a distinct 
species and is almost certainly a comparatively recent immigrant 
from some part of the Oriental region. It is a very abundant 
and distasteful species, but it appears to have done little in the 
way of drawing other forms into resemblance to itself, and 
is the only abundant and wide-ranging Danaine in the country 
which has not become the centre of an association. 
It is true that there is one species which does bear a 
considerable resemblance to it, but the mimicry is not nearly 
so close as in the other cases we have been considering. This 
species is Papilio leoyiidas which, I may remark, has a form 
in South Africa which resembles Amauris echeria and another 
form which is not mimetic at all. We seem to have here an 
interesting case of incipient mimicry, and it is worthy of note 
that the model is in all probability a recent invader whilst the 
mimic is, so far as we know, an old inhabitant. Such cases as 
these, and they are known to occur in other regions, are an 
insuperable difficulty in the way of interpreting these resem 
blances as due to the influence of local causes, whilst they 
afford the strongest possible support to the theory of mimicry, 
since the invader which is able to draw after itself original 
Vol I. — No. 2. 
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