FLIES OF THE GENUS AGROMYZA, RELATED TO 

 AGROMYZA VIRENS. 



By J. R. Malloch, 



Of Urhana, Illinois. 



The species dealt with in this paper belong to a group which is 

 distinguished from all others in Agromyza by the black halteres. 



When at work upon the species of Agromyza in the collection of 

 the United States National Museum in 1913, I had considerable 

 difficulty in finding characters by means of which the numerous 

 closely allied species could be separated and had to use minute ones 

 which had not previously been given in descriptions of species of the 

 genus. Because of this departure from previous usage, and also 

 because I realized that I was dealing with a large and complex group 

 and not with merely a few widely distributed species, I refrained 

 from associating but one of them with European forms. Just prior 

 to the appearance of my paper ^ one by Prof. A. L. Melander ap- 

 peared,^ in which are given the names of several species of this group 

 which belong to the European forms, but which are also said to 

 occur in America. I have aheady given my reasons for refusing to 

 adopt the course taken by Professor Melander^ and believe that, inde- 

 pendent of the fact that identifications of European species described 

 by the old authors in this group are only guesses up to the present, 

 from the existence of such a large number of very closely allied 

 species I am justified in my refusal to recognize American species as 

 synonymous with those of Europe until we know to what European 

 formes certain names really belong. I have accepted the European 

 species schineri as occurring in eastern Canada and Massachusetts 

 because the description agrees with that given by Giraud, but more 

 especially because the larvse of the European species and that of the 

 specimens from Massachusetts both make galls on twigs of poplar. It 

 is not my purpose to deal with questions arising from the publication 



1 Ann. Entom. Soc. Amer., vol. 6, No. 3, Sept., 1913. 



2 Journ. N. Y. Entom. Soc, vol. 21, No. 3, Sept., 1913. 



3 Entom. News, vol. 25, 1914, p. 308. 



Proceedings U. S. National Museum, Vol. 49— No. 2097. 



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