DIPTERA 379 



considerably on the submarginal cell; halteres whitish; length, 1.5 

 mm. Tagus Cove, Albemarle, March 23. Two specimens. 

 Type. — Cat. No. 4715, U. S. National Museum. 



Family HIPPOBOSCID^. 



PSEUDOLFERSIA DIOMEDE^ sp. nov. 

 Head brown; a transversely-oval, elevated, polished, frontal spot 

 reaching slightly below the middle of the front ; a transverse parallelo- 

 grammatic one occupying the lowest median fourth of the front ; 

 orbits elevated and polished ; remainder of the front depressed, opaque, 

 gray pruinose ; shorter hairs of antennae yellow, the stronger ones dark 

 brown, changing into yellow at their apices ; thorax polished brown, 

 the angles yellow, the sides, transverse suture, a spot towards the middle 

 of the thorax from each humerus and a second spot a short distance 

 behind each of these, also two spots in front of the scutellum, opaque, 

 gray pruinose ; middle of sternum yellow ; scutellum polished dark 

 brown, destitute of bristles, posteriorly truncate and ciliate with very 

 short hairs ; abdomen dark brown, opaque, gray pruinose ; wings 

 hyaline, veins brown, the first vein, except its base, usually yellow, 

 last section of the fifth vein and the whole of the sixth except its base, 

 whitish ; apex of first vein noticeably before the small crossvein, apex 

 of second vein about twice as far from the apex of the first vein as from 

 tip of the third ; legs brown, the lower side of the femora and the 

 tibiae except their outer and inner edges, yellow ; length 7 mm. Albe- 

 marle, March i. Four specimens, taken on an albatross {^Diotnedea 

 irrorata Salvin). 



Type. — Cat. No. 4431, U. S. National Museum. 



PSEUDOLFERSIA FOSSULATA Macquart. 



Olfersia fossidata Macquart, Dipt. Exot., 11, p. 434, 1842. 



Wenman, December 13. A single specimen. Originally described 

 from Brazil. 



Proc. Wash. Acad. Sci., November, 1901. 



