ADAPTIVE COLORATION 231 



" 2. That many, probably most species, dislike, if not in- 

 tensely, at any rate in comparison with other butterflies, the 

 warningly-colored Danainae, Acrcea mo Ice, Delias eucharis, and 

 Papilio aristolochice; of these the last being the most distaste- 

 ful, and the Danainse the least so. 



" 3. That the mimics of these are at any rate relatively 

 palatable, and that the mimicry is commonly effectual under 

 natural conditions. 



" 4. That each bird has separately to acquire its experience, 

 and well remembers what it has learned. 



" That therefore on the whole, the theory of Wallace and 

 Bates is supported by the facts detailed in this and my former 

 papers, so far as they deal with birds (and with the one mam- 

 mal used). Professor Poulton's suggestion that animals may 

 be forced by hunger to eat unpalatable forms is also more 

 than confirmed, as the unpalatable forms were commonly eaten 

 without the stimulus of actual hunger generally, also, I may 

 add, without signs of dislike." 



Though insects have many vertebrate and arthropod ene- 

 mies, it is probable that the evolution of mimetic resemblance, 

 implying warning coloration, has been brought about chiefly 

 by insectivorous birds. 



Neglecting papers of minor importance, we may pass at 

 once to the most important contribution upon this subject 

 the voluminous work of Marshall and Poulton upon mimicry 

 and warning colors in South African insects. These investi- 

 gators have found that birds are to be counted as the principal 

 enemies of butterflies ; that the Danainse and Acrseinae, which 

 are noted as models, are particularly immune from destruc- 

 tion, while unprotected forms suffer; and that mimicking, 

 though palatable species, share the freedom of their models. 

 The same is true of beetles, of which Coccinellidae, Mala- 

 codermidae (notably Lycus), Cantharidse and many Chryso- 

 melidse serve as models for many other Coleoptera, being 

 " conspicuous and constantly refused by insect-eaters." In 

 short, the splendid work of Marshall and Poulton tends to 



