most minute examination that I could convince myself it was not so." And of a leaf-butterfly he says: "We find representations of leaves in every stage of decay, variously blotched and mildewed, and pierced with holes, and in many cases irregularly covered with powdery black dots, gathered into patches and spots, so closely resembling the various kinds of minute fungi that grow on dead leaves that it is impossible to avoid thinking at first sight that the butterflies themselves have been attacked by real fungi."
Mimicry is the resemblance which poorly protected animals bear to others well protected. Several species of edible butterflies imitate the Heliconidæ and others, which are protected by fetid odors; other
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butterflies mimic wasps so closely that persons fear to handle them, although the imitation does not extend to the sting. Innocent beetles imitate other beetles which have hard shells or fetid glands. They also mimic bees and wasps. Flies also mimic wasps, and grasshoppers mimic beetles. Some moths almost exactly imitate the form and color of hummingbirds. Wallace states that some harmless snakes