PUP^ OF COMMON SPHINGID^ OF EASTERN 

 NORTH AMERICA.* 



By Edna Mosher." 



Since beginning the study of pupae it has been necessary 

 many times to try to prove that a classification based on pupal 

 characters should indicate natural relationships just as well as 

 a study of the adults. There are still too few persons who 

 believe that anything can be gained from a study of the biology 

 of a species, or that a classification based on the immature 

 stages of a group offers any aid in the solution of problems 

 relating to the adults. It seemed to me, therefore, that a study 

 of so compact a group as the Sphingidae, upon which such a 

 careful study of the adults of the world species has been made 

 by Rothschild and Jordan- in their masterly revision of the fam- 

 ily, would offer some evidence on this vexed question. The study 

 has confirmed in practically every detail the classification of 

 Rothschild and Jordan. It has shown the same relationships, 

 and practically the same degree of relationship existing between 

 the various species. In some cases it was not possible to sep- 

 arate satisfactorily very closely related genera and species, 

 which serves to illustrate another idea about pupee which seems 

 to me to be an absolute fact, namely, that the pupa is slower to 

 change than either larva or adult and therefore indicates the 

 ancestry and relationships of a species or genus better than any 

 of the other stages. 



Since the Sphingidae contain the largest, as well as some of 

 the most interesting lepidopterous pupae, it also seemed worth 

 while to make it possible for any one to identify the commoner 

 forms. It has not been possible to rear all of the species to 

 verify identifications, but practically all of the material not 

 reared by the author was reared by Mr. William Beutenmueller, 

 a well-known authority on the subject. 



Except where especially mentioned the materials used in 

 this study are in the collection of the University of Illinois or 

 in the author's private collection. 



* Contributions from the Entomological Laboratories of the University 

 of Illinois, No. 58-. 



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