38 



V. A List of the North American Syrphidae 



BY CH. R. OSTEN SACKEIST. 



[Read before this Society, Nov. 5, 1875.] 



Ijf tins second instalment of a new Catalogue of North American 

 Diptera,' I have followed, in the main, the plan of the first, to 

 which I refer for the necessary explanations. This part, perhaps 

 more than the first, bears the double character of a compilatory 

 and synonymical catalogue. It brings together all the species, pub- 

 lished before and after my catalogue of 1858; at the same time, it 

 gives the synonymy, as far as I have succeeded in working it out. 

 My success in this respect depended, of course, on the material at 

 my command, and as the collections within my reach are almost 

 exclusively from the United States, that part of the catalogue is 

 better purged of synonymy than the lists of the Cuban and Mexi- 

 can species. 



The species, as far as practicable, are referred to the proper genera. 

 Species which I do not know, nor could identify, even generically, 

 from the descriptions, were, of course, left where I found them. 



I deemed it useful to add, in the notes, references to Mr. Loew's 

 numerous monographic papers on European genera, the study of 

 which papers will be indispensable in working up the corresponding 

 American genera. Some other notices and references which I give, 

 may also be welcome to the student. Among them I will mention 

 the data about the geographical distribution of the species, which 

 I have collected wherever I could. 



The total number of described Syrphidae from North America, 

 north of Mexico, and exclusive of California, which are actually 

 identified and contained in our collections, is now about one hun- 

 dred and sixty. Of this number, ninety-one species, that is, more 



« The first was : A List of the Leptidae, Mydaidae and Dasypogontna of North America, 

 published in this Bulletin in October, 1874. 



