NO. I BLACK FLIES OF GUATEMALA — DALMAT IO3 



basal third of second tarsal segment light brown, the apical parts of 

 these segments, as well as all of segments 3-5, dark brown. Leg 3, 

 length, 3.5 mm. ; coxa dark brown ; trochanter brown ; femur brown, 

 with dark-brown apex; basal three-fourths of tibia, except for one 

 margin, light brown, the apical fourth dark ; tarsus dark brown ; rela- 

 tion of basitarsus to second segment, 8.0 : i ; basitarsus long, narrow, 

 parallel-sided ; calcipala very large, wide, pointed at end ; pedisulcus 

 absent. 



Abdomen: Tergite of segment i light brown, somewhat gray- 

 pruinose, with short yellow hairs ; pleurites light brown, with long 

 yellow hairs that reach segment 5. Segment 2 dark brown, the an- 

 terior half white-pruinose, clothed with yellow hairs. Other seg- 

 ments dark brown, the posterior margin lighter, clothed with both 

 short and long yellow hairs. Sternites dark brown, gray-pruinose, with 

 yellow hairs. 



Genitalia : Sidepieces (pi. 22, fig. 10) longer than wide, somewhat 

 cylindrical in shape; the basal and apical margins at angle to each 

 other ; with concavity on dorsal surface near middle of apical end ; 

 dorsal opening occupying more than half of dorsal surface of side- 

 piece. Clasper (pi. 22, fig. 10) conical in shape, about three-fourths 

 the length of sidepiece ; apex rounded, with two terminal spines, one 

 distal to the other ; basal opening extending along less than half of 

 clasper. Body of adminiculum (pi. 22, fig. 11) almost square in shape, 

 slightly longer than wide, the apical corners rounded ; with concavity 

 at middle of apical margin; longitudinal keel extending entire length 

 of body along middle of ventral surface ; entire body of adminiculum 

 clothed with short hairs, longer on keel-like structure ; basal processes 

 short, broad, poorly sclerotized, each with a spurlike process directed 

 posteriorly. Adminicular arms (pi. 22, fig. 12) small, with 2 teeth, i 

 very long, the other about three-fourths its length ; lateral plate minute, 

 irregular in shape. 



Female (pi. 28, figs. 127-129, and pi. 35, fig. 272). — (First descrip- 

 tion of female.) 2.9 mm. long. 



Head : Dichoptic ; elongate. Eyes black, shiny ; f ronto-ocular tri- 

 angle very small, its height about equal to its base. Antenna 610 /u, 

 long, II -segmented, slightly tapering, the apex blunt; segment 

 3<i+2, 3<44-5, 3 = 11; scape and pedicel yellow, flagellum brown, 

 its apex very dark. Palpi dark brown to black. Frons, clypeus, and 

 occipital region black, gray-pruinose, with short and long yellow hairs. 

 Cornuae of buccopharyngeal apparatus sclerotized, wide, bifurcate, 

 the two branches pointed ; median space hyaline, smooth. 



Thorax: Mesonotum reddish brown, with slight gray pruinosity 



