44 PROCEEDINGS OF THE NATIONAL MUSEUM vol.79 



orbitals present; sides of abdomen black and the apex red, second 

 segment bearing one pair of stout median marginal bristles; other- 

 wise similar to male. 



Length, 9.5 to 13 mm. 



Type. — In the British Museum of Natural History. 



Redescribed from 15 males and 10 females in the United States 

 National Museum, all collected at Summit, Canal Zone (J. Zetek), 

 and labeled " ex Arsenura er'ythrinae Fabr." One female from 

 Higuito, San Mateo, Costa Rica (Pablo Schild), is apparently the 

 same. In the American Musemn of Natural History there are 24 

 specimens, including both sexes, from Chaj^ada, Brazil (H. H. 

 Smith). The males of this series have the outer genital forceps 

 broader at the apex and somewhat longer but there appear to be 

 no other tangible characters differing from the remainder of the 

 material examined. 



(26) WINTHEMIA XANTHOCERA Wiedemann 



Plate 1, Figure 6 



Tachina xanthocera WiEa)EMANN, Auss. Zweifl., vol. 2. p. 329, 1830. 



Masipoda xanthocera Wiedemann, Brauer and Bergenstamm, Denk. Wien. 



Akad. Wiss., vol. 56, p. 163, 1889 ; vol. 58, p. 402, 1891 ; vol. 60, p. 123, 1893. 

 Exorista ochracea van der Wuu>, Biologia Dipt., vol. 2, p. 63^ 1890. 

 Exorista rubricornis van der Wltlp, Biologia Dipt., vol. 2, p. 66, 1890. 

 Exorista sororcula van dee Wulp, Biologia Dipt., vol. 2, p. 68, 1890. 

 Winthemia xanthocera Wiedemann, Aldrich, Proc. U. S. Nat. Mus., vol. 72, 



p. 14, 1927. 



Orbital bristles present in both sexes, claws and pul villi minute; 

 ocellars often poorly developed and sometimes wanting; apical joint 

 of fore tarsi in female somewhat swollen but not noticeably elongated. 



Male. — Front broader than usual with the sides almost parallel, at 

 vertex 0.306 of the head width (average of three: 0.29; 0.32; 0.31) ; 

 median stripe reddish brown, broad to triangle and occupying one- 

 third of the frontal width ; paraf rontals gray pollinose, very sparsely 

 haired from vertex downward; frontal bristles about 8 in number, 

 extending below the middle of second antennal joint, uppermost two 

 or three bristles stout and reclinate; inner verticals strong, nearly 

 erect, the outer ones about two-thirds as long; face silvery, the sides 

 narrow, bearing only a few slender hairs on the inner margin; 

 vibrissae situated on level with oral margin; palpi yellow, bearing 

 numerous short black bristly hairs; antennae almost reaching oral 

 margin, basal joints blackish, third largely red, about three times the 

 length of second; arista distinctly longer than antennae, hardly at 

 all thickened toward base, color red to middle and darker beyond, 

 penultimate joint very short; cheeks red in ground color, gray polli- 

 nose and covered with moderately long black hairs, about one-seventh 

 the eye height ; posterior surface of head thickly pale-haired. 



