DIPTERA— STRATI0MYIDJ3. 567 



lower margins of the wing, and the auxiliary and first longitudinal veins, 

 though closely approximate, are pretty distant from and parallel to the mar- 

 gin through most of their course. 



Length of body, S-""; of wing, 4.5"""; breadth of thorax, 1.5""; of 

 abdomen, 1.9""'; of wing, 1.75"". 



Green River, AYyoming. One specimen. No. 4 (Dr. A. S. Packard). 



ASARCOMYIA gen. nov. (a-, adpH, ju^ia). 



This genus, also belonging to the section Beridina, is distantly related 

 to Chiromyza Wied. Head slightly narrower than the globular thorax. 

 Abdomen long, composed of seven joints, with nearly parallel sides, broader 

 than the thorax. Antennae with short basal, long and equal second, joint. 

 Legs long and very slender, the tibiae with a short row of spines near the tip, 

 the apical ones no longer than the others. Wings with the third longitudinal 

 vein simple, the first longer than the second basal cell, the discoidal cell emit- 

 ting three long and nearly straight veins to the border, all arising apically, 

 a fourth vein arising from the second basal cell ; fifth and sixth longitudinal 

 veins uniting close to the margin. 



The simple third longitudinal vein, tlie unequally long basal cells, and 

 the fourth branch of the fourth longitudinal vein with its origin from the 

 second basal cell apart from the others, are characteristics which do not 

 seem to be combined in any other genus. The discoidal cell is small, 

 longitudinal, arched, situated a little above the middle of the wing. 



ASARCOMYIA CADAVER. 

 PI. 9, Fig. 17. 



Whole body and wings of a nearly uniform testaceous color, the thorax, 

 legs, and principal veins of the wings a little darker. Metanotum with two 

 large approximated basal bristles. The wings are tolerably broad, the cos- 

 tal margin nearly straight most of the way to the tip, the auxiliary vein 

 reaching to a little beyond the middle of the wing, the second longitudinal 

 arising from the third a little sooner, or at about the middle, and ending 

 after a gently sinuous course considerably less than midway from the tip of 

 the auxiliary to the tip of the arcuate third longitudinal vein. First basal 

 cell closed scarcely beyond the tip of the auxiliary, at the middle of the 

 discoidal cell. (In the figure the cross-vein before this is an accidental mark 



