CHAPTER V. 



PROTECTIVE MIMICRY, 



Mr. Bates' Theory. 



THE theory of warning- colours is believed to obtain very 

 strong support from a series of remarkable facts of which 

 an adequate explanation was first offered by Mr. Bates.* 



This naturalist spent many years in South America, being- 

 principally engaged in studying the Lepidoptera of that 

 country. Among the most abundant butterflies in the 

 Amazonian region are those of the family Heliconidaj ; the 

 prevailing pattern of these insects' wings is shown in the ac- 

 companying woodcut (fig. '24'}. The contrast between yellow 

 and black suggests at once that they belong to that group 

 which are protected from attack through being distasteful : 

 this suggestion is, to a certain extent, borne out by Mr. Bates* 

 observations. He found in the first place that they could 

 secrete from certain glands in the abdomen a disagreeably 

 smelling fluid ; it does not, however, follow from this fact 

 alone that the butterflies would prove disagreeable to the 

 palate of a lizard or a bird : many animals are attracted b\ 

 odours which to us appear in the highest degree objectionable. 

 An attentive observation of the butterflies convinced both 

 Mr. Bates and Mr. Wallace that they were avoided, or at 



Transaction* of tht /,'//>/ ";/ Nor/ ///, vol. xxiii. 



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