Contributions to the theory of natural selection. A series of essays ... By Alfred Russel Wallace ...

110 AIIMICRY, AND OTHER PROTECTIVE
influence all groups related to each other in an equal
degree. Again, the general fact that those species
which mimic others are rare, while those which are
imitated are abundant, is in no way explained by either
of these theories, any more than is the frequent occurrence of some palpable mode of protection in the
imitated species. " Reversion to an ancestral type"
no way explains why the imitator and the imitated
always inhabit the very same district, whereas allied
forms of every degree of nearness and remoteness
generally inhabit different countries, and often different quarters of the globe; and neither it, nor
"C similar conditions," will account for the likeness between species of distinct groups being superficial onlya disguise, not a true resemblance; for the imitation
of bark, of leaves, of sticks, of dung; for the resemblance between species in different orders, and even
different classes and sub-kingdoms; and finally, for the
graduated series of the phenomena, beginning with a
general harmony and adaptation of tint in autumn and
winter moths and in arctic and desert animals, and
ending with those complete cases of detailed mimicry
which not only deceive predacious animals, but puzzle
the most experienced insect collectors and the most
learned entomologists.
Mfimicry by Female Insects only.
But there is yet another series of phenomena connected with this subject, which considerably strengthens
the view here adopted, while it seems quite incompa