ADAMS: NORTH AMERICAN DIPTERA. 451 



Of some of the synonymy given by Mr. Coquillett in this 

 group I am not prepared to approve or disapprove. Some of 

 the species removed by hira from this genus, however, I be- 

 lieve belong more properly to it than to any other. 



Urellia flava, n. ep. 



Female : Body wholly covered with yellow pollen ; head and 

 members yellow, arista and frontal bristles black, those of the 

 occiput yellow. Thorax yellow, the mesonotum appears through 

 the pollen to be black in ground color, metanotum likewise 

 black, short pile yellow, bristles of mesonotum and scutellum 

 black, latter two in number, halteres yellow. Abdomen yel- 

 low, the last two segments appear through the pollen to be 

 blackish, ovipositor subshining yellow, tip black, pile yellow. 

 Legs wholly yellow, with yellow bristles and pile. Wings very 

 much like those of U. abstersa Loew, but the reticulations on 

 proximal half are yellowish and become uniformly fused along 

 the first ray from the subapical spot, the anterior branch of 

 the Y-shaped mark at tip of wing is not connected with the ray 

 preceding it, between the Y-shaped mark and the third vein is 

 a deej) black spot which on transmitted light is opaque and 

 stands out from the surrounding less dark color, the same color 

 exists in the tip of the small ray ending at the apex of the sec- 

 ond vein, also in the apex of the short but broader ray preced- 

 ing ; otherwise the wing is as in U. abstersa Loew. Length, 3 mm. 



One specimen ; Bill Williams Fork, Arizona. Collected by 

 Dr. F. H. Snow. 



Urellia conjuncta, n. ep. 



Female : Head and members yellow, arista and frontal 

 bristles brownish black, those of the occiput yellow. Thorax 

 black, gray pollinose, humeri, a spot before base of wing, pile 

 and halteres yellow, bristles of mesonotum and scutellum black, 

 the latter two in number. Abdomen black, gray pollinose, sub- 

 shining, pile yellow, ovipositor shining black, with a few yel- 

 low pile at base. Legs yellow. The large spot on the wing has 

 all the rays in front of the fourth vein fused, emitting only five 

 rays on posterior side of this vein, the spot reaches along the 

 costa to a point half-way between a point opposite the small 

 cross-vein and tip of first vein, at which place it possesses a 

 small hyaline dot, in base of first posterior cell is a hyaline spot 



