The mockers and mocked always inhabit the same region; we never find an imitator living remote from the form which it imitates.

The mockers are almost invariably rare insects; the mocked in almost every case abounds in swarms.

In the same district in which a species of Leptalis closely imitates an Ithomia, there are sometimes other Lepidoptera mimicking the same Ithomia: so that in the same place, species of three genera of butterflies and even a moth are found all closely resembling a butterfly belonging to a fourth genus.

It deserves especial notice that many of the mimicking forms of the Leptalis, as well as of the mimicked forms, can be shown by a graduated series to be merely varieties of the same species; while others are undoubtedly distinct species.