CLASS V, I>^SECTA. 297 



seta (simple or slightly plumose) inserted beyond the dorsal jvmc- 

 tion of the second and third joints : head anteriorly distinctly rostri- 

 form. 



Sp. 1. Erist. Na7rissi. 



Jnliabits flowers in marshes. 



Genus 5'27. IlELOPIIILUS. Leach. Elopkilus. Mclg., Illig., 



Latr. 

 ^/ito»<rcontiguous at their base, their last joint broader than long; 

 seta (simple or slightly plumose) inserted beyond the dorsal juncture 

 of the second and third joints; head anteriorly distinctly rostriform. 

 Sp. 1. Hel. tenax. Latr., Leach. 

 Inhabits hedges, and is very common. 



Genvis .528. SYRPHUS of authors. 

 AntemuE separate at their base, their last joint suborbiculate : seta in- 

 serted beyond the dorsal junction of the second and third joints : 

 abdomen elongate-subquadrate, gradually somewhat narrower to- 

 wards its extremity. 

 Sp. 1. %?'. Pt/rastri. Fabr. 

 Inhabits flowers. 



Genus 529. DOROS. Meig., Illig., Leach. 

 Antenna si'parate at their base; their last joint suborl>iculate : seta in- 

 serted beyond the dorsal juncture of the second and third joints : ab- 

 domen subovate-trigonai ; the length double the breadth. 

 Sp. 1. Doros conopseus. 

 Milesia conopsea. Fabr. 

 Inhabits fields, but is very rare. 



SxiRPS 2. — Head not anteriorly conic-produced : antennee much longer 

 than the head, placed on a common elevation : oval caviti/ on the 

 nasal prominence : zcings deflexed. 



Genus 530. CHRYSOTOXUM. Meig., Latr., Leach. 

 Antenna subcylindric, their last joint having a seta at its base. 

 Sp. 1. Chri/s. arcuatum. 

 Musca arcuata. Linni. 

 Inhabits flowers. 



Genus 531. CERIA. Fabr., Latr., Illig., Meig., Leach. 

 Antemuv with their first and second joints forming an oval mass termi- 

 nated by a style. 



There is one British species, that does not seem to have been de- 

 scribed. 



Stirps 3. — Head not anteriorly produced: nasal part straight, not pro- 

 minent ; antenna inserted separately, very much longer than the 

 head : wings deflexed. 



Genus 53'2. APHRITIS. Latr., Leach. Microdon. Meig. 

 Antenncs with their third joint conic, elongate, its base bearing a seta. 



