4'' SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 5] 



Section MYODARIA 



Fmnt in both sexes of equal width, or if wider in female the greater width is 

 due to a widening of the frontalia and the tegtilae are absent; tegulae never 

 well developed (includes Conopidae) Subsection Holometoi'a 



Front in male narrower than in female, the wider front of female never due 

 to a widening of the frontalia, tegulae never absent; if the front is not 

 wider in female the tegulae are well developed. .Subsection Schizometopa 



Subsection SCHIZOMETOPA 



I lypopleural and pteropleural bristles and hairs always absent, fourth longi- 

 tudinal vein lying partly in the hind margin of the wing behind middle of 

 extreme wing-tip, proboscis never adapted for bloodsucking, if three 

 sternopleural bristles present their formula is 1:2. 



Super family AnthomyioihEa 



Either hypopleural or pteropleural bristles or hairs always present, fourth 

 longitudinal vein rarely continuous with hind margin of wing behind mid- 

 dle of extreme wing-tip except when proboscis is adapted for bloodsuck- 

 ing,' if three sternopleural bristles present their formula is either 2:1 

 or 1:1:1 Superfamily Muscoidea 



Superfamily MUSCOIDEA 



Facial plate strongly produced below vibrissal angles like the bridge of the 

 nose, the produced portion convex laterally and not flattened, the vibrissae 

 separated by this bulging and situated high above the oral margin; the 

 mesofacial plate and epistoma completely fused into one piece. 



(Phasiid Stem) Family Phasiilu-: 

 Facial plate not so produced, at most projecting nose-like below with flattened 

 . or if latter is somewhat convex (Gymnosomatinae) the vibrissae 

 are inserted quite near oral margin. 



I 

 I 



Facial plate always receding below vibrissal angles and oral margin never 

 prominent, thus giving the facio-peristomal profile an evenly and gently 

 convex outline: vibrissal angles situated at or above the lower two-thirds 

 point between oral margin and base of antennae, always very much higher 

 above median oral margin than length of second antennal joint, at least 

 twice as high, the mesofacial plate in consequence greatly shortened, never 

 widely produced downward, if not completely cut off by vibrissal angles 

 then at least very strongly constricted thereby, the peristomalia either 

 approximated and forming parallel lines for a considerable distance or 

 bowed outwardly and more or less widely separated so as to enclose the 

 epistoma as a more or less distinct sclerite of the facial plate between 

 them; antennae almost always very short. . (CEsTrid-Macronychiid Stem) 



A 



1 Mesembrina and Eumesembrina are the only exceptions known to th< 

 writer, aside from the bloodsucking forms. 



