192 MUSCID.E. 



Corpus oblongum, sublineare. Oculi rotundi. Antennamm articulus 

 tertius sublinearis, apice rotundatus ; sextus nudus. Alse sat angustaB. 

 Body oblong, nearly linear, with few hairs and bristles. Face flat, 

 bare. Peristoma small, round. Eyes round. Third joint of the an- 

 tennae nearly linear, rounded at the tip, more than twice the length of 

 the second ; sixth bare. Wings rather narrow. Costal vein ending 

 on the hind border near the tip ; subcostal a little shorter than the medi- 

 astinal, which ends a little beyond one-third of the length ; radial end- 

 ing very near the tip ; cubital and preebrachial parallel ; discal trans- 

 verse straight and upright, parted by more than twice its length from 

 the prsebrachial transverse, and by more than its length from the border. 

 Abdomen with five apparent segments, hardly longer than the thorax. 

 These flies inhabit herbage. 



1. aridella, Fal. Ochtid. 10. 2 (1820) ; Meig. ; Mcq. ; Zett. Cano- 

 tomentosa, alis limpidis, abdomine immaculato, tibiis flavis. Long. 1|- ; 

 alar. 3 lin. 



Black, with hoary tomentum. Wings limpid. Abdomen unspotted. 

 Legs yellow ; femora, except the tips, and tarsi towards the tips black. 

 Generally distributed. (E. S. I.) 



2. juncornm, Fal. Ochtid. 9. 1 (1820) ; Meig.! Zw. vi. pi. 59. 

 f. 11 ; Mcq. ; Zett. Cano-tomentosa, alis limpidis, abdomine e maculis 

 nigris bivittato, tibiis flavis. Long. 1 ; alar. 3 lin. 



Black, with hoary tomentum. Wings limpid. Abdomen with three 

 black spots on each side. Legs yellow ; femora, except the tips, and 

 tarsi towards the tips black. 



Generally distributed. (E. S. I.) 



The following additional species have been recorded as British: 



1. poly stigma, Meig. 3. geniculata, Hal. 



2. flavipalpis, Hal. 



SUBFAMILY 4. OBTALIDES. 



ORTALIDES, Hal. ; Westw. Class. Ins. i. 148 (1839). Ortalides, Fal. 

 Ortalides et AciphorecB, Fal. ; Zett. TepTiridita, Bigot. 



Alarum vents subcostalis et mediastinalis non conjunct^, areola pobra- 

 chialis et analis sat longce. Abdomen sessile. Pedes longitudine me- 

 diocres. 

 Subcostal and mediastinal veins separate. Pobrachial and anal areokts 



not short. Abdomen sessile. Legs of moderate length. 



a. Palpi thick. 



b. Colour not metallic. 1. PLATYSTOMA. 

 b b. Colour metallic. 2. ULIDIA. 



