460 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 43. 



One female, Plummers Island, Maryland, 27-6-09 (W. L. McAtee) ; 

 one female. Holly Springs, Mississippi (F. W. Mally). The enlarged 

 bristle on mesopleura separates it from the next species, and the 

 points enumerated in description from xantippe Banks, which is most 

 closely allied to it. 



Type.— Cat. No. 14846, U.S.N.M. 



APmOCH^ffiTA ARCUATA, new species. 



Female. — Black, distinctly shining; frons shining, slightly gray 

 pollinose, longer than broad, upper post-antennal bristles small and 

 veiy close together, occupying about one-seventh the breadth of 

 frons, lower pair minute, center pair of bristles in first row slightly 

 lower on frons than upper post-antennals and midway between them 

 and outer paii* in first row which are very slightly higher on frons, 

 center pair in second row about one-fifth the distance from ocellar 

 triangle to post-antennal bristles, antennse very small, brown, arista 

 very short, barely two-thirds as long as frons, bare, palpi dusky yellow, 

 of moderate size, weakly but numerously bristled ; disk of thorax very 

 fliickly covered with minute hairs, mesopleurae with numerous 

 bristles, two or three of which on the lower posterior margm are 

 distmctly longer than the others, scutellum with four bristles, the 

 anterior pair weaker than the posterior; abdomen broad and rather 

 short, egg-shaped, broadest at apex of second segment, second and 

 third segments with several short lateral hairs, the others almost 

 bare; legs piceous, fore coxae and all tibiae paler, hind femora with 

 rather long hairs on ventral surface, mid tibise without setulse, hind 

 tibiae very strong, the dorsal ridge very distinct causing the dorsal 

 surface to present an arcuate appearance when viewed laterally, 

 setulse distinct; wings distinctly infuscated, costa to middle, first 

 division distinctly, but not greatly, longer than other two together, 

 third one-third as long as second, fringe nearly as long as fork of 

 third vein, very delicate, fork of third vein acute, fourth vein very 

 slightly bent at base and regularly arcuate, ending distinctly in 

 front of wing tip ; halteres yellow. 



Length 2 mm. 



One female. Cabin John Bridge, Maryland, April 28, 1912 (Knab 

 andMalloch). 



Type.— Cat. No. 14847, U.S.N.M. 



APmOCHiETA NIGRICEPS Loew. 



Yellow; frons dull black, four post-antennal bristles, the lower pair 

 half the size of the upper, antennae black-brown, of moderate size, 

 arista pubescent, palpi yellow, large, distinctly bristled, thorax yellow, 

 indistinctly striated, scutellum with four almost equal-sized bristles, 

 mesopleurae with a number of small bristles on upper posterior angle; 

 abdomen with only the base of the first segment and the apices of the 



