A REVISION OF THE NORTH AMERICAN SPECIES OF 

 ICHNEUMON-FLIES BELONGING TO THE GENUS METE- 

 ORUS HALIDAY. 



By C. F. W. MuESEBECK, 



Of the Bureau of Entomology, United States Department of Agriculture. 



INTRODUCTION. 



In this paper, which is a contribution from the gypsy moth and 

 brown-tail moth division of the Bureau of Entomology, an attempt 

 has been made to define the limits of the braconid genus Meteorns 

 Haliday, and to prepare a key which will enable the worker in the 

 parasitic Hymenoptera to identify the North American species of 

 this group. Incidentally it was found necessary to describe a num- 

 ber of new species, several of which appear to be common. 



The task of revising the genus was undertaken because the group 

 is an important one economically and at the same time has been badly 

 confused. Owing to the extreme variability of the species, erroneous 

 determinations have been many; and host records that have been 

 published are, in considerable part, incorrect. Fortunately, the 

 collection in the United States National Museum, at Washington, 

 District of Columbia, upon which this work is largely based, has 

 extensive reared series of most species; and a good deal of additional 

 material reared at the gypsy-moth laboratory at Melrose Highlands, 

 Massachusetts, was also available. This has helped immeasurably 

 in the selection of characters which will be found useful for the 

 separation of species. 



The types of most of our species are in the collections of the United 

 States National Museum and the Philadelphia Academy of Sciences. 

 To these and the types of the thi'ee species in the Connecticut Agri- 

 cultural Experiment Station, in New Haven, Connecticut, I have 

 had access. I have had no opportunity, however, of studying the 

 following: The types of Provancher's species, which are in the 

 Museum of Public Instruction, in Quebec, Canada; those of three of 

 Viereck's species which are in the collection of Kansas University; 

 that of hakeri Cook and Davis, which appears to have been lost; that 

 of vitticollis Holmgren, which was evidently placed in a European 



No. 2470.— Proceedings U. S. National Museum, Vol. 63, Art. 2. 



1 



