482 PROCEEDINGS OF THE NATIONAL MUSEUM voL-m 



1st and 2d A; inner gradates of 1st r and 1st r-m, usually six outer 

 gradates of 2d r, s, r-m, 2d m between MA and MPl+2, ra between 

 MPl + 2 and MP3+4, m-cu; thyridia usually apparent in centers of 

 radiomedial and medial cross-veins, and sometimes on sectoral cross- 

 veins. 



Male genitalia (fig. 18,a-d): Eighth tergite longer dorsally, not 

 as broad as ninth; ninth tergite divided mediodorsally, of diverse form; 

 tenth tergite broader than long, divided mediodorsally into two 

 lateral plates; eighth sternite about as long as or slightly shorter and 

 narrower than seventh sternite, usually with an anterior group of 

 very long setae projecting posteroventrally and with their bases 

 hidden under posterior portion of seventh sternite; ninth sternite 

 entire, ventral to ninth and tenth tergites, frequently with a pair of 

 posteriorly projecting processes on inner surface, more or less em- 

 bedded in a hyaline membrane; tenth sternite posterior and postero- 

 ventral to tenth tergite, in the form of narrow plates, usually broad- 

 ening ventrally and internally, and covered with toothlike projections 

 bearing long setae; parameres arising within the posterior part of the 

 eighth, and the ninth and tenth tergites, partially fused, complex, 

 usually bearing a median lobe or flap, which diverges abruptly 

 anterodorsally from the posterior portion of plate, a pair of curved 

 hooklike processes posteriorly. 



Female genitalia (fig. 18, e): Eighth tergite usually divided mid- 

 dorsally and appearing fused mid ventrally; ninth tergite typically 

 divided into two large plates, each moved latero ventrally to the 

 tenth tergite, heavily sclerotized, usually longer than broad and 

 with a posterior ridge for articulation with ninth sternite; tenth 

 tergite entire, small, broader than long, thickly covered with long 

 setae, frequently shorter dorsomedially ; ninth sternite divided into 

 two elongate movable upturned parts projecting and tapering more 

 or less dorsally, usually bent posteriorly just before apex, each half 

 articulated ventrally at posterior articulation ridge of ninth tergite, 

 with small narrow ventral projection; tenth sternite not accounted 

 for. 



Basal abdominal segments. Second to fifth tergites usually 

 smaller and shorter than sixth and seventh, often rounded (chapini, 

 nota); fom-th to seventh tergites sometimes oval {carpenteri, chilena, 

 nota); second sternite large, usually with V-shaped streak, with each 

 half beginning along lateral margins, sometimes just posterior to 

 center (basalis, carpenteri, chapini) or in posterior corners (nota) and 

 curving anteriorly to meet in point just before anterior margin; third 

 sternite with streak with each half beginning in posterior corners 

 and meeting other half in center of sternite so almost parallel with 

 anterior margin; fourth sternite with streak usually almost parallel 



