PROCEEDINGS OF THE UNITED STATES NATIONAL MUSEUM 



issued |^?(ViL. sj^^ii h ike 



SMITHSONIAN INSTITUTION 



U. S. NATIONAL MUSEUM 



Vol. 106 Washington : 1956 No. 3373 



A REVISION OF THE ACROCERID FLIES OF THE GENUS 

 PIALEA ERICHSON WITH A DISCUSSION OF THEIR SEXUAL 

 DIMORPHISM (DIPTERA) 



By Evert I. Schlinger' 



While preparing a revision of the family Acroceridae (C3Ttidae) 

 only five specimens of the genus Pialea were located for study, even 

 though more than 6,000 specimens of the family had been borrowed 

 from the various museums throughout the world. Because of the 

 taxouomic confusion caused by the sexual dimorphic trait of this 

 genus, and since specimens are apparently quite rare in collections 

 and not often brought together for study, a revision of Pialea seems 

 in order at this time. 



I wish to acknowledge aid from the following people, who have 

 contributed specimens and comments for this project: Prof. Max 

 Beier of the Vienna Naturhistorische Museum, Austria; Prof. Willi 

 Hennig of the Deutsches Entomologisches Institut, Berlin; Dr. S. L. 

 Hora of the Zoological Survey of India in Calcutta, and Mr. Curtis W. 

 Sabrosky, Entomology Research Branch, U. S. Department of Agri- 

 culture. Thanks are also due Dr. R. M. Bohart and Mr. Sabrosky 

 for reviewing the manuscript. The drawings have been prepared by 

 the author. 



Department of Biological Control, University of California, Riverside, Calif. 



359 



386752—56 



