VOL.76 TWO-WINGED FLIES OF THE GENUS COELOPA ALDPaCH 3 



valid European species to which the name may be applied. Mr. 

 Collin, however, says that gravis and parmda always occur together, 

 which casts doubt upon the validity of the latter. 



I have omitted Coelopa anomala Cole ^, from Lower California, 

 which is said to have a convex thorax instead of the flattened one 

 which is so characteristic in the genus, and probably does not belong 

 here. At any rate the form of the thorax will separate it. 



KEY TO NORTH AMERICAN SP.BCIES OF COELOPA 

 MALES 



1. First vein with a few liairs on apical part ; middle tibiae pilose, the others- 



spiny (California, Oregon) vanduzeei Cresson. 



First vein entirely bare 2. 



2. All femora and tibiae with dense, long soft pile, like that of middle 



basitarsus, not at all bristly (Bering Sea) stejnegerl, new species. 



All femora and tibiae spiny in the larger specimen,^*, bristly in the smaller, 

 but in all case.s the pile of the middle basitarsus is evidently much softer 

 and more delicate than this 3. 



3. Abdomen with spiny bristles not only on sides and hind margin but scattered 



over the disk of the last three segments (Bering Sea region). 



nebularum, new species. 



Abdomen with spiny bristles only on hind margin and sparsely on sides 



(North Atlantic Coast) gravis Haliday. 



FEMALES 



1. First vein with a few hairs on apical part (California and Oregon). 



vanduzeei Cresson. 

 Fix'st vein entirely bare 2. 



2. Legs usually blackish (North Pacific Coast) 3. 



Legs reddish yellow (North Atlantic Coast) gravis Haliday. 



3. Cheek with dense, soft, rather short hair ; arista minutely setulose under 



high power stejnegeri, new species. 



Cheek with sparser hair, which is somewhat bristly above; arista not 

 minutely setulose nebularum, new specie.^. 



COELOPA GRAVIS Haliday 



Coelopa gravis Haliday, Entomological Magazine, vol. 1, 1833, p. 167. 

 Coelopa frigida Osten Sacken, Catalogue N. A. Dipt., 1878, p. 197 (not of 



Fabricius). — Hagen, Canad. Ent., vol. 17, 1885, p. 140. — Johnson, List Dipt. 



New Eng., 1925, p. 248; Proc. Bost. Soc N. H., vol. 38, 1925, p. 95. 

 Coelopa eximia Stenhammar, Copromyzinae, 1855, p. 318. 

 Coelopa nitidula Osten Sacken, Catalogue N. A. Dipt., 187S, p. 197 (not of 



Stenhammer). 

 Coelopa parvula Johnson, List Dipt. New Eng., 1925, p. 248 (not of Haliday) ; 



Proc. Bost. Soc. N. H., vol. 38, 192,5, p. 95.— Sturtevant. Biol. Bull., vol. 50, 



p. 83. 



I have examined 22 specimens from tlie New England coast — 

 Massachusetts and Rhode Island. Johnson writes me, " They do not 



sproc Cal. Acad. Sci., vol. 12, 192.3, p. 470. 



