104 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.49. 



of Professor Melander's synopsis of this genus, but I am not inclined 

 to consider it as even possible for simjjlex Loew and tibiae Couden to 

 be varieties of maura Meigen. The larvae of the latter makes galls 

 upon twigs of linden, while simylex^ mines in stems of asparagus. 

 The foregoing statements are not made with any intention of criti- 

 cising Professor Melander's work, but merely to justify my own 

 attitude with regard to the use of European species names until we 

 are in possession of reliable information as to what species these 

 names really apply to. As a further evidence that extreme care is 

 required when identifying specimens belonging to this group, I present 

 the facts contained in this paper. I was obliged, when working upon 

 the paper previously referred to, to request Mr. C. W. Johnson to 

 examine the type of Agromyza virens Loew in Museum of Compara- 

 tive Zoology in Cambridge, Massachusetts, and report to me upon 

 certain characters. Mr. Jolmson kindly 'did so, and upon his infor- 

 mation I based my identification of Loew's species. I had, however^ 

 a strong suspicion that I had more than one species before me, though 

 the material was not sufficient to permit me at that time forming a 

 definite opinion. Since coming to Illinois I have upon every occa- 

 sion collected specimens of this group, until I have before me at the 

 present time a series of three species which enable me to come to a 

 conclusion with regard to their identity. A fourth species sent me 

 by Prof. F. M. Webster is also included, which I have not succeeded 

 in obtaining here. I give a synopsis of the four species below. 

 This synopsis may be inserted in that which is given in my paper 

 already referred to at the points in table where the name virens 

 occurs. 



The type-specimen of gihsoni and paratypes, with exception of 4 

 specimens in the collection of the Illinois State Laboratory of Natural 

 History, have been returned to the Bureau of Entomology. The 

 type-specimens of the other 2 new species are in the former collec- 

 tion, while paratypes will be deposited with the Bureau of Ento- 

 mology. 



Synopsis of Species. 



a^ Last section of Gf th vein at least as long as penultimate section . . riparia, new species. 



Last section of fifth vein distinctly shorter than penultimate section a". 



a^ Five pairs of orbital bristles present; frons not noticeably buccate. 



svhvirens, new species. 



Four pairs of orbital bristles present a?. 



a^ Frons buccate; eyes of male distinctly hairy, of female pubescent above; last sec- 

 tion of fourth vein 3-3 J times as long as penultimate virens. 



Frons not buccate; eyes of male bare or slightly pubescent a*. 



a* Outer cross vein slightly bent; last section of fourth vein 5 to G times as long as 

 penultimate gibsoni. 



Outer cross vein straight; last section of fourth vein 3-4 times as long as penultimate. 



cupatoriae. 



> J. E. Collin in his paper on British Muscidae Acalyptratae (Ent. Mon. Mag., vol. 22, 1911, p. 254) treats 

 simplex and maura as distinct species. 



