NEW GENERA AND SPECIES OF MUSCOID FLIES. 



By Charles H. T. Townsend. 



Custodian of Muscoid Diptera, United States National Museum. 



In the following descriptions the position of hind crossvein is 

 stated with reference to its relative distance from the small crossvein 

 and the cubitus as nearer to one or the other, or in the middle be- 

 tween them. 



The holotypes of all the new species described are in the United 

 States National Museum, excepting only those of Trocliiloglossa 

 tropica, Myothyriofsis hivittata, and Neoerigone cinerea, which are in 

 the American Museum of Natural History; while paratypes of the 

 last two are in the National Museum. 



The forms are arranged systematically under tribes, to conform 

 with the arrangement adopted in synoptic tables of muscoid genera 

 which it is hoped may be i:)ublished within the year. 



Tribe MUSCININI. 

 NEOMUSCINA, new genus. 



Genotype. — Neomuscina cavicola, new species. 



Differs from Muscina as follows : Clypeus strongly dished. Arista 

 much longer than antennae, thinly plumose. Female frontalia 

 without convergent pair of bristles in front of ocelli. Cheeks not as 

 wide as epistoma. Only one preacrostichal bristle. Scutellum sub- 

 pointed behind. Basal segment of abdomen well shortened, the 

 anal segment little longer than preceding segment. Third segment 

 with a marginal row of erect bristles. 



NEOMUSCINA CAVICOLA, new species. 



Length, 7 mm. Numerous specimens of both sexes, but largely 

 males, from the Santa Catalina, Chiricahua, Graham, and Pinal 

 Mountains, and the East Verde River, all Arizona, 3,500 to 5,500 

 feet. (C. H. T. Townsend); and females from Las Vegas Hot 

 Springs, New Mexico (H. S. Barber). The males especially congre- 

 gate in quantity during the day in caverns and under overhanging 

 rocks in the canyons, often entering the tent at night. 



Proceedings U. S. National Museum. Vol. 56— No. 2301. 



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