NO. I BLACK FLIES OF GUATEMALA — DALMAT 133 



two-thirds ; R2+3 pilose except for very small basal section ; Cug 

 arcuate ; discal cell absent. 



Legs: Leg i, length, 2.3 mm.; entire leg light brown except the 

 tarsus which is black. Leg 2, length, 2.0 mm. ; coxa bluish black ; tro- 

 chanter light brown ; femur light brown with bluish-black apex ; tibia 

 tan with blackish cast ; basitarsus tan with black cast apically ; tarsal 

 segment 2 with basal half light brown, apical half black ; segments 

 3-5 black. Leg 3, length, 2.4 mm. ; coxa and trochanter light brown ; 

 femur light brown with somewhat darkened apical end ; basal half of 

 tibia light brown, the apical half black with numerous black hairs; 

 basal two-thirds of basitarsus and basal half of second segment tan, 

 the remainder of these segments, as well as all of segments 3-5, black ; 

 relation of basitarsus to second segment, 4.8 : i ; calcipala well de- 

 veloped, reaching the pedisulcus ; pedisulcus well formed at basal third 

 of second segment ; small claw with almost no basal heel, but with 

 small subbasal tooth (pi. 35, fig. 265). 



Abdomen : Tergum of segment i pale yellow, with short yellow 

 hairs ; pleurites pale yellow, with long tan hairs that reach the third 

 segment. Segment 2 pale yellow. Segments 3-6 yellowish, with gray 

 pruinosity, each segment with large velvety-black patch in middle of 

 dorsal surface and with i or 2 small patches lateral to the median one ; 

 segments 7 and 8 pale yellow. Sternites tan. 



Genitalia: Cercus (pi. 29, fig. 145) somewhat higher than long 

 (wide), with few long, strong hairs and numerous short, spinelike 

 hairs. Anal lobe (pi. 29, fig. 145) rather narrow (short), extending 

 beneath the cercus, with posteriorly directed, ventral, fingerlike pro- 

 jection which is more heavily sclerotized than the rest of the anal 

 lobe and contains many very short hairs and some rather long ones. 

 Genital rod (pi. 29, fig. 147) with small, bulblike basal dilatation; 

 apical expansions of arms of genital fork triangular in shape, the inner 

 basal angle broad and blunt, the apical angle tapered and pointed ; both 

 these angles sclerotized along the arms ; a rather long, heavily sclero- 

 tized, toothlike process arising from middle of outer margin ; margin 

 sclerotized between this process and the apical angle. Ovipositor 

 (pi. 29, fig. 146) small, 32 /x long by 8-10 /t at widest point, somewhat 

 lyre-shaped. 



Pupa (pi. 36, fig. 285, and pi. 39, fig. 325). — Granulosity on entire 

 thorax ; 5 bifid trichomes on either side of midline, all on anterior half 

 of thorax. Dorsal surface of abdominal segments : No granulosity ; 

 spines on segments 2-4 are anteriorly directed, those on segments 6-9 

 are posteriorly directed ; segment 2 with 8 simple, hairlike spines in a 



