Art. 12 THE FLY GENUS SARCOPHAGA ALDEICH 9 



and strongly differentiated from remainder of frontals, which are 

 in five pairs, the upper minute, the lowest at extreme base of an- 

 tennae and not farther apart than the preceding pairs; facial ridges 

 bare, converging somewhat at vibrissae, which are at oral margin; 

 Palpi black, cheek two-fifths of eye-height. Antennae black, 

 second joint fully half the third and a little reddish at tip. Frontal 

 stripe mostly overlaid with the silvery pollen of the parafrontals. 



Thorax gray, not strongly striped. Chaetotaxy : Dorsocentral 2, 3 ; 

 acrostichal 2, 0; humeral 2; posthumeral 1; presutural 1; supraalar 

 3 (only the middle one large) ; intraalar 2 (far back) ; postalar 2; 

 sternopleural 1, 1; scutellum with 2 lateral, 1 small subdiscal, no 

 apical. Propleura bare. 



Abdomen subsilvery, tessellated, with 3 irregular darker stripes. 

 No median marginals on first and second segments; third with mar- 

 ginal row of 8 small ; fourth with larger row of 8. Genital segments 

 black, large, so that the depth of the abdomen increases from base 

 to tip; the second segment is directly below the first, so that the 

 suture is almost horizontal, and extends considerably forward under 

 the abdomen, fitting closely into the main segments. Genitalia (fig. 

 24) small, red; forceps united into a small, slender beak; accessory 

 lobes well developed, forming an outer pair of forceps as long as the 

 inner, swollen at base and a little at tip, and fringed with a row 

 of black bristles on the inner side; penis small, tip enlarged for- 

 ward; posterior claspers slender, with a sharp tip curved forward; 

 anterior claspers flat, narrowing to a sharp tip. 



Wing tinged with brown, epaulet black, basicosta red; first vein 

 setulose on basal half (in one specimen there is a strikingly large 

 seta almost at the end of the row, in both wings) ; third vein setu- 

 lose less than halfway to the crossvein ; fourth vein with rectangular 

 bend, the hind crossvein joining fourth closer to bend than usual, 

 about at the last fifth from anterior crossvein. Costal segment 

 between third and fourth equal to that between auxiliary and first. 



Legs black; middle tibia with 2 bristles on outer front side; all 

 tibiae without villosity; no comb on middle femur. 



Length 9.5 mm. 



Sarcophaga opima, p. 364. 



One male from the Vienna Museum, " Brasilien. Coll. Winthem." 

 Agrees with description and is undoubted type. It differs from the 

 genus Sarcophaga, and I would place it provisionally in Notochaeta, 

 although it lacks the hairs on the propleura which occur in the 

 type species. The parafacials are bare, and the notopleura lacks 

 the small bristles which alternate with the two large ones in Sar- 

 cophaga. The arista has very long plumosity nearly to the tip ; 

 the eye is large, so that the cheek is only one-fourth its height. 

 2662—30 2 



