208 THOMAS SAY FOUNDATION 



curved bristle; arista long-plumose for three-fourths 

 its length; facialia black, hairy for half their height; 

 palpi and proboscis black, ordinary; bucca golden 

 pollinose in front and covered with yellow beard, 

 which extends up the back of the head, there being 

 but two rows of black hairs behind the eye. 



Thorax whitish pollinose with 3-5 strong black 

 stripes, the submedian gray stripes divided narrowly 

 before the suture; ps dc 2, close to scutellum; ant dc 

 1, just before suture; ant acr none; prsc 1 ; stpl 3, the 

 intermediate small; scutellum with two large margin- 

 als and an apical but little smaller. 



Abdomen black, strongly tessellated; first three 

 segments with only lateral bristles; fourth with mar- 

 ginal row of nearly 20. 



Hypopygium deep red; first segment long, shin- 

 ing, with small row of bristles at apex; second seg- 

 ment shining, globose. Forceps long, black on apical 

 half or more, diverging at base and thence almost 

 parallel, strongly bent forward about middle, thence 

 nearly straight to the slender, sharp tips; accessory 

 plate large, oval, brown, thin and paler on hind edge, 

 excised at tip ; posterior clasper black, straight, blunt ; 

 anterior clasper very stout, strongly curved, black ex- 

 cept base. Penis yellowish-red, its basal segment 

 not visible; the distal segment smooth, with a square 

 end, from which on the front side arise two pairs of 

 long, irregular arms, the inner longer; from the hol- 

 low apex protrude three points, one unjDaired. Fifth 

 sternite widely excised, near the base on each side 

 forming a yellow ridge with short black brush; the 

 remainder concealed under the fourth tergite. 



Legs black; middle and hind tibife and femora 

 with dense long villosity ; middle tibia with one bristle 

 on outer front side. 



Wings hyaline; no costal spine; third costal seg- 

 ment longer than fifth and sixth together ; first vein 

 bare, third with a few hairs. 



Female. Front narrowest at vertex^ .240 of 

 head (one specimen), with the usual orbitals and 



