CYCLORRHAP-HA 



Family Empid^. 



Orthorrhapha brachycera with medium or small bodies and small heads. 

 Antennae with the first two joints very small and hardly distinct, the third 

 joint annulated, often with terminal bristle. Wings with three large complete 

 basal cells, of which the third is shorter than the second. The posterior basal 

 transverse vein is parallel to the border of the wing. Empodium membrana- 

 ceous. 



It is doubtful whether these insects attack man. As a rule they live on the 

 juices of other insects and plants. 



SUBORDER II. CYCLORRHAPHA. 



Section 1: Aschiza. — This group includes the family Syrphidse, 

 of which no species is known to bite man. 



Section 2: Schizophora. — This group includes the true flies 

 characterized by a distinct frontal lunula and a frontal suture; 

 antennae with three simple segments, and an arista which is generally 

 dorsal. They may be classified into — 



Muscoidea. 



Synonym. — Eumyidea. 



This superfamily is divided into: — 



Tribe i: Muscoidea acalyptratce, without squamse covering the 

 halteres. 



Tribe 2: Muscoidea calyptratce, with squamae covering the 

 halteres. 



MUSCOIDEA ACALYPTRATiE. 



A large number of families are grouped together under this 

 division, of which the most important for our purposes are — 



1. Sepsidae. 



2. Oscinidae. 



3. Drosophilidae. 



4. Borboridae. 



These families can be recognized as follows: — 



A. Subcostal (auxiliary) vein present. Radial i (first longi- 



tudinal) terminates near or beyond the middle of the 

 wing. 



I. With a distinct bristle on each side of the face near the 

 oral margin. 



Front never bristly near antennae; abdomen some- 

 what elongate, cylindrical, usually narrowed near 

 base. Small black flies found about decaying 

 matt er — S epsidce . 



B. Subcostal vein absent, vestigial, or incomplete. Radial i 



usually ends in the costa before the middle of the 

 wing. Head not produced into lateral processes. 

 I. Hind metatarsi incrassate and usually shorter than the 

 second joint — Borhoridce. 



