454 Prof. E. B. Poulton on the Mimetic N. American 



The evidence that Limenitis archippus occurs at 

 the same time and place as its model.* 



The following evidence (p. 455) bearing on the time and 

 space relationships of Limenitis archij^ims and its Danaine 

 model exists in the bionomic series of the Hope Department. 

 The most perfect data were those obtained on August 5, 

 1897, when, with my kind friends Professor W. M. 

 Wheeler (now of Harvard) and Professor S. Watase, I 

 had an excellent opportunity of witnessing the flight of 

 many examples of both model and mimic on the same 

 ground. 



One of the specimens, a female, captured on August 6, 

 1897, had evidently been visiting-the flowers of the food- 

 plant of its model ; for abundant Asclepiad pollen-masses 

 are attached to its limbs. 



The EVOLUTION or the mimetic pattern of L. archip- 

 pus FROM that of the non-mimetic L. arthemis. 



In the following interesting passage Scudder discusses 

 the general principles by which, as we may believe, this 

 remarkable transformation Avas effected : — 



" It is to be presumed that the actual colors found in 

 a mimicking butterfly are, with rare exceptions, such as 

 existed somewhere in the ancestral form. In the case of 

 our own mimicking Basilarchia, for example, whose orange 

 ground tint is so totally at variance with the general color 

 of the other normal members of the group, it will be 

 observed that all the normal species possess some orange. 

 Without this as a precedent fact, such perfect mimicry 

 might perhaps never have arisen. Individuals among the 

 normal species vary somewhat in this particular, so that 



* Much time and effort have been expended, during many years, 

 in the Hope Department, to induce naturalists in the field to collect 

 evidence beaiing on the coincidence in time and si^ace and on the 

 habits of mimetic species and their models, to breed the seasonal 

 forms of butterflies and accurately to record the times of their 

 appearance in nature. iMany of the results of this special study 

 have been publislied. So far as I am aware, systematic attempts of 

 the kind have been made by no other institution. I am bound to 

 assume that the editor of "The Entomologist's Record" is ignorant 

 of facts well known to probably every other student of insects in 

 this country. However this may be. any reader of that publication 

 can judge for himself how far the statements and inferences on pp. 

 189, 190 of the July number are true or false. — E. B. P., July 27, 

 1908. 



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