12 PROCEEDINGS OF THE NATIONAL MUSEUM vol.74 



distance before the ocelli, none reclinate, extending barely to the 

 antennae. Parafacial with delicate hairs in a single row. The 

 dorsocentral immediately before the suture and the last one before 

 the scutellum are much larger than those anterior to them. Abdo- 

 men without discals. Wing somewhat rounded, a well-developed 

 costal spine; first vein bare, rather short, ending just in front of the 

 small crossvein, the large crossvein straight and rather erect, joininer 

 the fourth vein half way between the crossvein and the bend, which 

 is obliquely rounded. Apical crossvein concave, the cell ending just 

 before the apex. 



CALLESTHES HISTRIO, new species 



Male. — The whole fly is opaque black with the following parts 

 white poUinose: the orbits, parafrontal, parafacial, face, a narrow 

 crossband on the thorax just in front of the suture which extends 

 forward at the sides to the hind edge of the humerus and obliquely 

 downward across the pleura to include the middle of the sternopleura 

 as far as the coxa; another white crossband just in front of the 

 scutellum extending laterally to the postalar calli and anteriorly 

 to the hindmost dorsocentral ; the second, third, and fourth abdomi- 

 nal segments have at the front edge a broadly interrupted narrow 

 crossband. 



Front 0.21 of head width at the narrowest part, which is a little 

 above its middle, the median stripe is very narrow especially toward 

 the antennae, where it is not more than one-third of the width of one 

 parafrontal. The parafacials are about as wide as the third antennal 

 joint. Antennae black, the third joint one and a half times the 

 second, the extreme base of the arista rather strikingly swollen, 

 suddenly becoming slender where the plumosity begins ; palpi black. 

 Cheek one-third the eye height, almost entirely bare, the transverse 

 impression soft and reddish. 



Thoracic chaetotaxy: acrostichal 3, 3 (all small); dorsocentral 2, 

 3; intraalar 2; supraalar 2 (the hind one hairlike); postalar 2; 

 humeral 2; posthumeral 1; notopleural 2; presutural 2 (the inner 

 minute); sternopleural 1, 1; scutellum with one large lateral and 

 one large apical, no distinct discal. First abdominal segment with 

 marginal row of bristles mostly rather small ; second segment with a 

 marginal row, the median pair and one lateral pair large; third 

 segment with marginal row of eight rather large; fourth segment 

 with a similar marginal row, no discals. 



Legs black, pulvilli brown, not much enlarged. Middle tibia with 

 one stout but not long bristle on outer front, two on outer hind side 

 and one flexor. Hind tibia with two bristles only on outer hind side; 

 same on inner hind side. 



