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their nauseous and conspicuous neighbours as to be mistaken for 

 them by insectivorous foes. I am not enough of an 

 entomologist to be able to pronounce with confidence some of the 

 imposing Latin names of the butterflies mentioned in works 

 dealing with protective mimicry. Let it suflBce, then, to say 

 that Bates discovered in Northern Brazil several kinds of con- 

 spicuous butterflies which were so much alike as to deceive even 

 a skilled entomologist, yet which were found upon close examina- 

 tion to be in no way related. Bates found that it was only their 

 conspicuous parts which had become altered so as to produce 

 resemblance. In their hidden and internal parts they each 

 conformed to the structure of their own proper section of the 

 insect world. Further investigation proved that wherever such 

 likenesses existed, one species was usually more numerous than 

 others, and moreover possessed certain qualities which rendered 

 them unfit for food, and fairly secure from attack. ... I. 

 have said that these conspicuous, and at the same time nauseous, 

 and otherwise formidable creatures profit by their bold advertise- 

 ment. It is not difficult to see where the gain comes in. We 

 are all acquainted with the provei'bs. " Once bit, twice shy," and 

 " A burnt child fears the fire." Now a bird which had once 

 had a painful experience in trying to eat one of these acrid 

 insects would hesitate ab'^ut attacking another exactly like it. 

 The insects, if one may so speak, make themselves as disgusting 

 as possible and proclaim the fact they are intolerably nasty by 

 every means in their power. 



In studying the subject of mimicry it has been found 

 necessary to divide it into two sections. One deals with 

 protective, mimicry in which insects and other animals, 

 themselves edible, gain iuimunity from attack by resembling 

 those which are nauseous ; the other with aggressive mimicry, 

 when the semblance of another creature is adopted, not for the 

 sake of eacaping enemies but for the sake of preying upon the 

 victims of deceit. 



To this latter class belong certain flies which almost exactly 

 resemble humble bees, and which steal into the nests of the 

 latter and lay their eggs in the bees' nursery, so that the larval 

 flies, when hatched, commence to dine upon the young bees 

 without going far in search of their food. Another instance, to 

 which attention was drawn by Mr. and Mrs. Packhara, the 

 American naturalists, to whom we owe the distinction between 

 protective and aggressive mimicry, is that of a spider which 

 assumes the exact shape of an ant, so that he may prey upon the 

 small beetle, which is one of the ant's domestic animals. 



