MIMICRY, WITH EXAMPLES 119 



According to Lewis,' who is in accord with Gadow, what 

 he interprets in the Viceroy butterfly is a transformation from 

 blue and black to a red, Hke that in the Monarch butterfly. 

 He assumes that this change occurs on the same theory that 

 the autumn leaves turn from green to yellow and red through 

 similar processes of chemical transformation, and he significantly 

 says: "If a crimson leaf of the red maple resembles one of the 

 Japanese ivy, it is not due to mimicry." Other facts have been 

 brought forward by Piepers, in reference to the theory of 

 mimicry. 



Poulton believes that the study of mimicry possesses special 

 advantages for an understanding of the history and causes of 

 evolution, and that North America is the most suitable area in 

 the world to begin its stu'dy. In one of his most recent articles ^ 

 among other interesting things, he has asserted that one of our 

 common black species of swallow-tail butterflies known as Phar- 

 macophagus philenor, is mimicked by three species of butter- 

 flies. These are the female of Papilio asterius, on both sides 

 of its wings; the black female of Papilio turnus (see page 147), 

 which is common in the southern part of its range, and both 

 male and female of Papilio troilus, shown in the frontispiece 

 illustration. From a study of these insects he was able to 

 point out that the latter species may be regarded as the oldest 

 mimic, asterius the next, and turnus (glaucus) the latest or 

 youngest in the order of their mimetic evolution. 



After summing up the bulk of the literMure on this subject, 

 and more especially the writings of Poulton, it is apparent that 

 mimicry seems to stand on a firmer basis than ever. More- 

 over, as Jordan and Kellogg aptly remark: "Whatever other 

 factors or agents have played a part in bringing about this 

 specialization of color and pattern, exemplified by animals 

 showing protective resemblance, warning colors, terrifying 

 manners, and mimicry, natural selection has undoubtedly been 

 the chief factor, and the basis of utility the chief foundation 

 for the development of the specialized conditions." 



'■American Naturalist, Vol. XLI, p. 782; see also DIxey's article in 



Nature. 



' "Annals of the Entomological Society of America," Vol. II, Dec, 1909. 



