AMERICAN DIPTERA. 285 



nounced on the apical margins of segments, and the brown 

 bases more opake, giving more contrast ; also the front is 

 more yellowish in color. A mutilated female from High- 

 rolls, N. M. ( Viereck, A. N. S.) , comes very near this species, 

 but the condition does not warrant its use as a type. The 

 abdomen is grayish laterally only, and the legs are more yel- 

 low, the tibiae being almost entirely so. 



This species, in size and general appearance, approaches 

 Loew's nigripes, but Dr. Hough says the hypopygium is cleft, 

 which is not the case with these specimens, thus suggesting 

 loewii Kertz (fasa'alus Lw.), from which it differs in having 

 the antenna? acuminate and the stigma longer than the fourth 

 section of the costa. 



4. B. confraternus Banks n. sp. 



Similar to P. subopacus, but the female has a very short ovipositor. 

 o". Face and front silvery ; antennae (Fig. 34) dark, with long white 

 tip to the third joint; occiput hoary; thorax brown-black, scutellum 

 more shining, sides barely hoary ; abdomen rather broad and flat, 

 nearly shining, but somewhat greenish-black, the basal segment hoary, 

 the sides of segments faintly hoary, legs pale, but femora with a broad 

 dark band, leaving base and apex paler. Wings (Fig. 139) gray hya- 

 line, stigma distinct, small cross-vein just below end of the auxiliary, 

 and slightly before end of basal third of cell. The last segment of ab- 

 domen is even from above and rather broad, the hypopygium bent 

 under and not at all promient. Length, 3.3 mm. ; wings, 3.8 mm." 



9 . Similar. Front with parallel orbits, shining black, silvery just 

 above antennae. Abdomen not flattened, nearly shining; ovipositor 

 short (Fig. 74), hardly longer than its base ; fifth segment longer than 

 fourth. 



Type—&. Sea Cliff, Long Island (Figs. 34, 72, 73, 139, 

 coll. Banks). 



Paratypes.— Sea Cliff, Long Island (1 d\ 1 9 , Fig. 74 coll. 

 Banks), Swarthmore, Pa. (1 C?, Cresson, A. A r . S.); Falls 

 Church, Va. (1 9 , coll. Banks) . Taken in July and August. 



In addition to the above description I note the following : 

 Humeri yellow ; halteres brownish-yellow ; abdomen more 

 or less brownish in certain aspects (I cannot distinguish any 

 greenish tinge) ; fifth segment of male only slightly longer 

 than fourth ; hypopygium more shining, lightly tinged with 

 gray and brown, very large (Figs. 72-73), semi-globose, 



TRANS. AM. ENT. SOC, XXXVI. DECEMBER, 1910. 



