TRANSACTIONS 



OF THE 



AMERICAN ENTOMOLOGICAL SOCIETY 



VOLUME XLV 



THE DIPTEROUS FAMILY CYRTIDAE IN NORTH ^ 

 AMERICA /\^ 



BY F. R. COLE 



U. S. Bureau of Entomologi/ 

 Introduction 



This paper is the result of about two years interrupted stud}' of 

 the dipterous family Cyrtidae. It is an interesting little group of 

 insects with a remarkable range of variation in structure. The 

 collecting of more material will no doubt cause some changes to be 

 made in the status of a few species, and further study will reveal 

 other characters for the separation of the different forms. 



The species of Cyrtidae are xqyj rare, at least until their 

 local haunts are known. In several places along the Pacific 

 Coast large series of Eulonchus have been collected, but these 

 are rarely found in any great numbers. The family is a small 

 one and some species are known from only one or two specimens. 

 Few collectors have any large number of these flies, and even 

 those who have made a search for them have found them only 

 at rare intervals. The species are not economically important, 

 those in which the early stages are known being parasitic in the 

 egg cases or in the bodies of spiders. In only a few species 

 have the early stages been found and we know nothing of the 

 life histories of some genera. 



Several entomologists have at one time or another made a 

 1 Published by permission of the Secretary of Agriculture. 



TRANS. AM. EXT. SOC, XLV. 



