3g Orthorrhapha brachycera. 



group 3 ; obscura has uniserial dorsocentrals, but biserial acrostichals ; 

 tibieUa and plumipes have distinct, biserial dorsocentrals, but pennata 

 and dentipes have distinctly uniserial dorsocentrals, these species could 

 scarcely remain in the same natural group; culicina and hyhrida have 

 distinctly observable acrostichals, tiigripennis and umhripennis have, I 

 think, none; variahilis has likewise no acrostichals but long dorso- 

 centrals; gibha finally has ordinary, very short pubescence almost 

 without rows. 



Tahle of Species. 



1. Eyes in the male separated; wings in the female with 

 the discai cell very large, or if not, w^ith two spots 

 below it; colour of the body not yellow nor shining 



black 2. 



— Eyes touching in the male; if slightly separated the 

 colour of the body is yellow or shining black; wings 



in the female with a normal discai cell 4. 



2. Thorax with four distinct stripes 2. nigripes. 



— Thorax only with two distinct stripes 3. 



3. Male -without yellow hairs at the end of the hind 



tibiæ ; female with the discai cell reaching to the margin 3. spissirostris. 



— Male with yellow hairs at the end of the hind tibiæ ; 



female with a normal discai cell 4. dissimilis. 



4. Wings in the male a little broadened, in the female 

 very broad with a brown seam; hind tibiæ and the 

 two first tarsal joints in the male with very long 



hairs and bristles 1. p?fli//pi(?r«. 



Wings not broad or only somewhat broad in the 

 female; hind tibiæ in the male not with so long hairs. . . 5. 



5. Dorsocentral bristles pluriserial 6. 



— Dorsocentral bristles bi- or uniserial 8. 



6. Halteres brownish; male with thin, whitish hind tibiæ 

 and tarsi, and with a very large, whitish, somewhat 

 bladder-like appendage at the genitalia; female with 



broad, brown wings and somewhat ciliated hind legs 7. vesiculosa. 



— Halteres pale; hind legs of the male normal; wings 



in the female not broad, hind legs not ciliated 7. 



7. Wings strongly brownish tinged; male with a spine- 

 like tuft of bristles at the base of the hind femora; 



female without spine-like bristles below the hind femora 5. spinipes. 



— Wing less tinged; male without any spine-like tuft at 

 the base of the hind femora ; female with short, spine- 

 like bristles below the hind femora 6. sulcata. 



8. Dorsocentral biistles biserial 9. 



— Dorsocentral bristles uniserial, or (in 5'«Z)&a) not observable. . . 14. 



9. Acrostichal bristles uniserial; legs in the female not 



pennate 8. conformis. 



— Acrostichal bristles biserial ; legs in the female pennate, 

 except in simjjlex 10. 



