NORTH AMERICAN STENOMIDAE — DUCKWORTH 25 



As mentioned earlier, Me3'^rick's system of classification was based 

 primarily on wing venation. He also tried to employ a hypothesis, 

 based on a mathematical formula, to provide a convenient artificial 

 system to which he could fit his classification. The desired standard 

 in Meyrick's classification was an average of about 10 species to the 

 genus and 50 genera to the family in the world fauna. His failure 

 to accept classification based on other valuable structures, such as 

 the genitalia, left many unanswered questions concerning relation- 

 ships of categories within the Stenomidae and relationships of this 

 family to other families. 



The relationship between Stenomidae and Xyloryctidae has pre- 

 sented a difficult problem; Busck (1921a) transferred the genus 

 Setiostoma ZeUer from Glyphipterygidae to Stenomidae. Forbes 

 (1923) evidently felt the two families were not distinct because he 

 listed them as subfamihes under the family Xyloryctidae. Clarke 

 (1955a) recognized them as separate famihes: the Xyloryctidae being 

 confined principally to the Old World and the Stenomidae to the 

 New World. 



The genus Stenoma Zeller, upon which the family is based, is still 

 a doubtful entity. The type species, Stenoma litura Zeller, is based 

 on a single female now in the British Museum that, according to 

 Clarke (1955a), is unlike any of the approximately 600 species that 

 have been placed as congeners. Clarke (1955a) also states that this 

 gi'eat mass of species is still a heterogeneity that will require close 

 study, with the possible delimitation of many new genera based on 

 diagnostic refinements. 



Some genera that have been considered to be doubtful with respect 

 to family affinity are herein treated as Stenomidae on the basis of 

 the genitaha, pending a more comprehensive study of generic rela- 

 tionships throughout the family. In this paper, the family Sten- 

 omidae in North America includes the genera Stenoma, Antaeotricha, 

 Setiostoma, Mothonica, Menestomorpha, and Menesta. The genus 

 Menesta was moved by Forbes (1923) from the family Gelechiidae to 

 the Stenomidae on the basis of the genitalia, as well as other adult 

 and pupal characters. 



The author gratefully acknowledges the aid of Dr. David A. Young 

 of North Carolina State College, who encouraged the undertaking of 

 a taxonomic problem in the Microlepidoptera and made suggestions 

 on the preparation of this paper. Sincere thanks are also due Dr. 

 J. F. Gates Clarke, Head Curator of Entomology, U.S. National 

 Museum, for suggesting this problem, for technical advice, and for 

 his kind encouragement. The loan of material from their respective 

 private collections by Mr. C. P. Kimball and by Dr. Ronald Hodges 

 also is gratefully acknowledged. The author also wishes to thank 



