ORDER DIPTERA: THE BRACHYCERA 137 



at base, and the wings are profusely scribbled with fine 

 curved markings ; Pangonia {sens, lat.), Fig. 43, in which the 

 3rd antennal segment is composed of 8 subsegments and 

 is not angulated or toothed at base, and the proboscis is 

 usually elongate — being in some species several times longer 

 than the body ; and Chrysops (Fig. 44), in which all 3 seg- 

 ments of the antennae are long, the 3rd segment being 

 composed of 5 subsegments. All these genera are represented 

 severally in all the great zoogeographical regions of the 

 world, as also is the genus Silvius. 



The following synopsis of the genera of Tabanid(S is taken 

 from Miss Gertrude Ricardo's Revision of the family in the 

 A nnals and Magazine of Natural History, 1 90 1 - 1 904 : — 



Synopsis of Genera (^ Tabanidae. 

 I. Tabanina. 



I 



\ 



CTliird antennal segment composed of 4 subsegments or rings, and 



not angulated or spurred at base = 2. 



Third antennal segment composed of 5 subsegments or rings = 5. 



(Rings so distinct that the whole antenna appears to consist of 6 

 segments Hexatoma, Meigen (Europe). 



Rings not so distinct as to modify the appearance of the antenna 

 = 3- 

 r Wings with a profusion of ring-like and scroll-like markings 

 ' H^MATOPOTA. 



Wings not scribbled with circles and scrolls = 4. 



First and 2nd antennal segments pubescent in the male, 3rd seg- 

 ment longer than the 1st ; eyes hairy 



= Dasybasis, Macquart (Chili and Australia). 

 rFirst antennal segment globose, situated on a frontal protuberance 

 5. \ = Bolbodimyia, Bigot (Venezuela). 



I First antennal segment not globose = 6. 



, (Third antennal segment not angulated or toothed at base = 7. 



iThird antennal segment angulated or toothed at base = 9. 



'Body covered with metaUic scales 



= Lepidoselaga, Macquart {^Hadrus, Perty] (South America). 



7. \ Body metallic in colouring = Selasoma, Macquart (South America). 



Body not in any way metalhc ; 1st antennal segment longer than is 



usual in Tabanus ; wings usually with brown markings = 8. 



(Antennae long, the 3rd segment cylindrical and situated on a pro- 

 jecting tubercle = Udenocera, Ricardo (Ceylon). 

 Antennas not as particularised in Udenocera 

 = Diachlorus, Osten Sacken (America and Philippines). 



