NO. I BLACK FLIES OF GUATEMALA — DALMAT 245 



surface dark brown ; tarsus black. Leg 2, length, 2.8 mm. ; coxa 

 brown ; trochanter tan ; femur tan with apical black ring ; tibia tan on 

 basal two-thirds, apical third black ; tarsus black. Leg 3, length, 3.5 

 mm. ; coxa brown ; trochanter tan ; femur with basal three-fourths tan, 

 the apical fourth black; tibia tan on basal third, apical two-thirds 

 black ; basal half of basitarsus and basal fourth of second tarsal seg- 

 ment brown, the remainder of these segments, as well as all of seg- 

 ments 3-5, black; relation of basitarsus to second tarsal segment, 

 3.8 : I ; calcipala well developed, reaching the pedisulcus ; pedisulcus 

 present, but not deeply incised. 



Abdomen : Tergite of segment i black on anterior half and brown 

 on posterior half, clothed with short black hairs ; pleurites black, with 

 long tan hairs reaching segment 5. Segment 2 dark brown, white- 

 pruinose, with short black hairs. Other segments black, the pleura 

 partially white-pruinose ; tufts of black hairs on pleura of segments 

 3-5. Sternites tan. 



Genitalia: Sidepiece (pi. 26, fig. 97) subquadrangular in shape, 

 somewhat wider than long, with protuberance from outer posterior 

 angle ; dorsal opening occupying about half of the surface of sidepiece. 

 Clasper (pi. 26, fig. 97) about five times as long as it is wide, nar- 

 rowed toward the middle ; longitudinal projection on outer margin of 

 dorsal surface extending from the base about halfway to the apex ; 

 apex truncate, with a single, strong, terminal spine near its end. Body 

 of adminiculum (pi. 26, fig. 98) quadrangular, wider than long, its 

 basal processes long, broad, well sclerotized, and pointed ; on its ven- 

 tral surface, the body of the adminiculum has a longitudinal keel which 

 is clothed with numerous hairs ; there is a small apical concavity which 

 also bears several hairs. Arms of adminiculum (pi. 26, fig. 99) with 

 1 5-20 teeth, mainly concentrated at the apex to form a crown ; 3 very 

 long teeth closer to the lateral plate, i broadly triangular tooth near 

 apex; lateral plate subquadrangular in shape, wrinkled, slightly 

 sclerotized. 



Female (pi. 33, figs. 217-219, and pi. 35, fig. 252). — (First descrip- 

 tion of female.) 3.0 mm. long. 



Head : Dichoptic. Eyes black ; fronto-ocular triangle very small, 

 its height equal to the base. Antenna 510 /«. long, 11 -segmented, taper- 

 ing; segment 3<i-|-2, 3>4 + 5> 3=ii; scape and pedicel brown, 

 flagellum black. Palpi black. Frons black, white-pruinose, with 3 

 irregular rows of black hairs along lateral margins. Clypeus dark 

 reddish brown, white-pruinose, irregularly covered with black hairs. 

 Occipital region black, covered with short tan hairs. Cornuae of 

 buccopharyngeal apparatus well sclerotized, somewhat expanded ; 



