LIST OF DIPTERA. 299 



curved, ending on the bind border far from tbe tip of tbe wing. 

 Four complete separate externo-medial veins. Subanal vein united 

 to the anal at some distance from the border. Discal areolet elon- 

 gated, hexagonal. 



I. Hexatoma bimaculata. 



Nigra ; abdomen basi ylaucescens ; tibiae albce ; alee hyalince. 



Hexatoma bimaculata, Meig. 



a. Interlacken, Switzerland. Presented by F. Walker, Esq. 



Genus 18. RHAPHIORHYNCHUS. 



Caput depressum, thorace angustius. Epistoma referens pro- 

 cessum subulatum, acutum, apice oblique cleorsum directum. Ocelli 

 tres. Proboscis retracta, capitulo parvo compresso, inter palporum 

 basim conspicua. Palpi exserti, basi approximate apice divergentes 

 biarticulati ; articulus lus brevissimus ; 2us quadruplo longior, 

 crassus, subfusiformis, apice paulum incurvus. Antenna? approxi- 

 mate, porrectae ; articulus lus perbrevis, subcylindricus ; 2us' bre- 

 vissimus, cyathiformis. 



Rhaphiorhynchus, Wied. Dipt. JExot. i. 60. 



I. Rhaphiorhynchus planiventris. 



Sordide lilacinus ; thorax fusco trivittatus ; abdomen ferrugineum, 

 fusco limbatum ; tibice fiavce ; alee flavescentes . 



Rhaphiorhynchus planiventris, Wied. Dipt. JExot. i. 60, 1 ; Auss. 

 Ziveifl. ii. 106, 6. Macq. Dipt. JExot. i. 1, 170, 1, pi. 20 

 f.2. 



Brazil. 



Genus 19. ACANTHOMERA. 



Caput mediocre, crassum, thoracis latitudine. Facies utrin- 

 que sulco profundo, tuberculo subconico medio. Ocelli tres. Pro- 

 boscis retracta, parva. Palpi exserti, biarticulati, pilosi; arti- 

 culus lus cylindricus ; 2us subulatus, lo aequalis. Antenna? 



