4 Is Mimicry Due to Natural Selection ? (January, 
of very frequent occurrence, and, in a very large number of in- 
stances, are obviously not “‘ mimetic” nor of any apparent ser- 
vice to the “‘ mimicking ” species. As a justification for this as- 
-sertion, I may refer to a perfectly unexceptionable authority, 
namely, one of the best known advocates of the theory of 
natural selection, Mr. A. R. Wallace. In his inaugural address 
to Section D at the recent meeting of the British Association at 
Glasgow,! Mr. Wallace adduces the following illustrations of 
this law: “ Our first example is from tropical Africa, where we 
find two unrelated species of butterflies belonging to two very 
different families (Mymphalide. and Papilionide) characterized 
by a prevailing blue-green color not found on any other conti- 
nent. Again, we have a group of African Pieride, which are 
white or pale yellow with a marginal row of bead-like black 
spots ; and in the same country one of the Lycenide is colored 
so exactly like these that it was at first described as a species of 
Pieris. None of these four groups are known to be in any way 
specially protected, a that the resemblance cannot be due to 
protective mimicry.” ‘*In another series of genera, all belong- 
ing to the Nymphalide, we have the most vivid blue ground, 
with broad bands of orange-crimson on a different tint of blue or 
purple, exactly reproduced in corresponding yet unrelated species 
occurring in the same locality; yet, as none of these groups are 
protected, this can hardly be due to mimicry. A few species of 
two other genera in the same country also reproduce the same 
colors, but with only a general resemblance in the masking. 
Yet again, in tropical America, we have species of Apatura 
which, sometimes in both sexes, sometimes in the female only, 
exactly imitate the peculiar markings of another genus confined 
to America. Here again neither genus is protected, and the sim- 
ilarity must be due to unknown local causes.” Mr. Wallace ad- 
duces several other instances of a similar character ; and even in 
the case of the very South American instances on which so much 
stress is laid by Fritz Miiller, and, before him, by Bates, admits 
that “this can hardly be true mimicry, because all are alike pro- 
tected by the nauseous secretion which renders them unpalatable 
to birds.” : 
In the abstract of Fritz Miiller’s article it is stated that ‘ Fritz 
Miiller insists, as all writers on the subject have done, upon the 
similar geographical distribution of the imitating and the imi- 
tated species as a necessary concomitant of mimicry.” If, there- 
1 See Nature, vol. xiv. page 403, September 7, 1876. 
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