. Elementary biology; an introduction to the science of life . The explanation that is sometimes given of this resemblance is as follows: The milkweed butterfly has a bitter or disagreeable taste, and therefore birds commonly avoid eating the insect. The viceroy belongs to a family that is commonly eaten by the birds, being suffi- ciently attractive to them. The resemblance between the viceroy and the monarch protects the former from the at- tacks of the birds. Of course it is not sup- posed by anyone that the viceroy butterflies have purposely mim- icked the monarch. It is only supposed that
. Elementary biology; an introduction to the science of life . The explanation that is sometimes given of this resemblance is as follows: The milkweed butterfly has a bitter or disagreeable taste, and therefore birds commonly avoid eating the insect. The viceroy belongs to a family that is commonly eaten by the birds, being suffi- ciently attractive to them. The resemblance between the viceroy and the monarch protects the former from the at- tacks of the birds. Of course it is not sup- posed by anyone that the viceroy butterflies have purposely mim- icked the monarch. It is only supposed that the resemblance, how- ever it may have come about, is of advantage to the insects. We do not understand how these resemblances, or others like them (see Figs. 174, 175), have come about. Some of the theories offered to explain them are discussed in Chapter LXXXIV. We are in doubt not only as to how such protective mimicry may have arisen ; we are also in doubt as to whether mimicry is in all cases protective. Professor Punnett, an English biologist, made a special study of this subject in Ceylon, where examples of mimicry are unusually abundant. He found, in regard to certain cases, that the model and its supposed mimic never occupied precisely the same area; at most, the two areas overlap more or less. In the second place, the com- mon birds, against which the mimicry is supposed to be protective, do not molest either the model or the mimic; but the lizards eat the mimic as well as the other members of the family, which are supposed to be defenseless. The only other serious enemy of these butterflies was a certain large fly that pierces the thorax of the insect and sucks the juices. But this fly, like the lizard, attacks the mimic and his defenseless cousins without discrimination. In other \\v,. 175. Supposed cases of mimicry /, Bombns peniisylvanicus, a bumblebee, mimicked by 2, Laphria tlioracica ; 3^ Vespa maciilata^ a wasp, mimicked by 4, SpUomyia fusca. In these cases th
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