1891.] 93 



than the third ; abdomen without seta? on the disc or middle of the 

 segments ; feet with the claws and pads (pulvilli) very small ; the 

 males are rather difficult to discriminate from the females. 



1 (2) (3) Abdomen quite black 1. ForsteriyM gn. 



2 (1) (3) Abdomen black, with narrow white bands 2. fasciata, Mgn. 



3 (1) (2) Abdomen red, with a dorsal black stripe. 



4 (5) Face dull, without glittering reflections 3. divisa, Mgn. 



5 (4) Face with white or yellow glittering reflections. 



6 (9) Abdominal dorsal stripe narrow. 



7 (8) Fourth abdominal segment black 4. capiiatajDe Greer. 



8 (7) Fourth segment red 5. trifar-ia, ZeWer. 



9 (6) Abdominal dorsal stripe wide. 



10 (11) Fourth abdominal segment only black 6. latei-alis, ZeWer. 



11 (10) Third and fourth segments black 7. ornata, Mgn. 



Gr. FOESTEEI, Mgn. 

 This fine species, usually the largest in the genus, has the head reddish-yellow, 

 ■with silvery reflections ; the antennae have the basal joints testaceous, and the third 

 black or grey ; the second joint of the arista is a little curved and rather longer than 

 the third ; the palpi are yellow ; the cheeks and chin are almost bare ; the thorax is 

 rusty-black, and indistinctly striped ; the scutellum is brownish-yellow ; the abdo- 

 men is shining blue-black, without any white bands or reflections ; the legs are 

 black, or nearly black, in this, as well as in all the other species in the genus. Bare. 



Gr. FASCIATA, Mgn. 



rii/iceps, Wlk. 

 This species is very similar to G. Forsteri, but is usually smaller, and has the 

 shining black abdomen marked with narrow white bands on the front edges of the 

 segments ; the thorax is also rather more distinctly striped, and the cheeks are more 

 hairy. Not common. 



G. DIVISA, Mgn. 



This species differs from all the others by having the frontalia and cheeks of 

 rather a dull yellow colour, without gloss or glitter ; the cheeks are thickly covered 

 with hair, the abdomen is of a transparent red colour, marked with a broad, dorsal, 

 black, longitudinal stripe, and with very narrow transverse white bands, which are 

 often indistinct. Rare. 



G. CAPiTATA, De Geer, Zett., End., non Mgn. 

 Three distinct species have been mixed together under this name, viz. : G. 

 capitata, G. lateralis, and G. ornata, so it is rather difficult to determine which is 

 the one named by De Greer ; upon reference, however, to his figure of this fly, I find 

 that it gives (though rude) a very characteristic delineation of a female specimen, as 

 described by Zetterstedt and Rondani ; therefore, I shall adopt their diagnosis. 

 Head, with frontalia, rather wider in the female than in the male ; face glistening 

 with yellowish-white reflections ; cheeks nearly bare ; antennse with the basal joints 

 testaceous, the third joints black or grey, and about four times the length of the 

 second in the male, and only about twice in the female ; arista with the second joint 



