Diptera 75 c 



Locality: Three male specimens, Nome, Alaska, August 21 and 24, 1916 

 "(F. Johansen). 



Both these European species are recorded herein for the -first time from 

 North America. 



FUCELLIN^. 



Fucellia Robineau-Desvoidy. 



The species of this genus are found along the margins of streams, on the 

 seashore, and on the shores of lakes. 



Fucellia punctipennis Becker. 



Fucellia piinclipennis Becker, JNIiddel. om Gronland, vol. 29, p. 411, 1908. 



This species was described from east Greenland and has not since been 

 recorded. All the specimens in the present collection were obtained at Bernard 

 harbour. Dolphin and Union strait, Northwest Territories, May 1916, and June 

 _ 18, 1915. Eleven specimens (F. Johansen). 



Fucellia ariciiformis Holmgren. 



Fucellia ariciiformis Holmgren, Kongl. Vetenskap. Forhandl., 1872, No. 6, p. 103. 



This species was originally described from Greenland. I have seen examples 

 from Pribilof islands. There are twenty-nine specimens in the present collec- 

 tion: nine from Bernard harbour. Dolphin and Union strait, Northwest Terri- 

 tories, taken May 19, 1916, May 20 and 22, June 25, and July 11, 1915; nineteen 

 from Demarcation point, Alaska, May 15, 1914; and one from Collinson point, 

 Alaska, June 20, 1914 (F. Johansen). 



SCATOPHAGIDy^. 



The larvse of most species of this family feed upon decaying vegetable 

 matter and manure. One North American species, Hydromyza confluens Loew, 

 mines, in the larval stage, in the stems of Nymphaea americana. The imagines 

 of many species are predaceous, feeding upon other small insects, and most of 

 them are found near water, particularly on the shores of rivers, lakes, and on 

 the seashore. Many species can be obtained only by very thorough sweeping 

 with an insect net over grasses and other herbage growing in ponds and along 

 their extreme margins. 



The Uterature on this family is in deplorable condition from the point of 

 view of one who has to identify species, and in order to make clear the generic 

 concepts of the writer I have drawn up a key to the genera, which is included 

 in this paper. 



Very many species of the family occur in northern latitudes — in fact the 

 family is essentially a northern one — and this key will be found useful in future 

 work on arctic Diptera. 



Some of the genera are proposed herein for the first time, and several are 

 recorded for the first time from this continent. 



Key to Genera. 



1. Species with three sternopleural bristles 2 



Species with two sternopleural bristles 5 



Species with one sternopleural bristle 7 



2 First wing-vein bristly on apical half; palpi without long apical britsle; arista short- 

 haired or pubescent; scutellum with two or four bristles; fore femora without 



closely placed or very strong antero-ventral bristles Orthochaela Becker. 



First wing-vein bare, or the species does not have all of the above characters 3 



