TABANHXE. 51 



are found attached to the stem of plants or on leaves, those of 

 the aquatic forms are found attached to rushes. The larvae 

 are carnivorous, feeding upon snails, other larvse, etc. They 

 have a distinct head. The body is eleven-jointed, often 

 encircled with retractile fleshy protuberances, sometimes de- 

 veloped only on the ventral side, the last segment with a ver- 

 tical breathing opening, or the last two segments forming a 

 stigmatic tube. Pupa free, living in the earth or in water. 



TABLE OF GENERA. 



1. Hind tibiae with spurs at the tip, sometimes small (Pangonina). . 2 

 Hind tibiae without spurs (Tabanina:) 7 



2. Third joint of the antennae composed of eight annul!, the first of which 



is only a little longer than the following ones. .... 3 



Third joint composed of five annuli, the first of which is much longer 



than the following ones ; ocelli present 6 



3. Front of female broad, with a large denuded callus; ocelli present. 5 

 Front of female narrow, ocelli present or absent 4 



4. First and fourth posterior cells closed (Central and South America). 



DICLISA Schiner. 

 Fourth posterior cell, at least, open. . . *PANGONIA Latreille. 



5. Eyes acutely angulated above ; Hippoboscid-like species. 



GONIOPS Aldrich. 

 Eyes not acutely angulated above ; not Hippoboscid-like. 



APATOLESTES Williston. 



6. Second joint of the antennae about half as long as the first; eyes in life 



with numerous small dots. . . . :. SILVIDS Meigen. 



Second joint of the antennae as long or but little shorter than the first 



joint ; wings with a dark picture : eyes in life with fewer, larger 



spots. . . .... . . CHRYSOPS Meigen. 



7. Third joint of the antennae without, or with a rudimentary basal pro- 



cess .... 8 



Third joint of antennae with a well-developed basal process. . 10 



8. Thorax and abdomen with irridescent tomentum ; all the tibiae dilated 



(Central and South America and West Indies). HADRUS Perty. 

 Thorax and abdomen without tomentum 9 



* Inclusive of Corizomura and Diatomineura Rondani. 



