106 LIST OF DIPTERA. 



North America. 

 4. Xylophagus americanus. 



Flavus ; aniennce nigra ; thorace nigro vittatus et maculatus ; ab- 

 domen rufum, incisuris Jtavis ; pedes Jlavi, femoribus posticis 

 apice tibiisque rufescentibus, tarsis anticis basi nigro-fuscis ; 

 alee limpidee. 



Xylophagus americanus, Wied. 

 United States. 



5. Xylophagus triangularis. 



Niger ; abdomen maculis trigonis schistaceis ; pedes lutei ; alee 

 hyalince, apice et apud venas transversas fuscescentes. 



Xylophagus triangularis, Say. ; Wied. 

 Missouri. 



6. Xylophagus persequus. 

 Xylophagus persequus, Diptera Saundersiana, Pt. 1, 1. 

 North America. 



South America. 



7. Xylophagus? vetustus. 



Foem. Niger; caput albo-tomentosum ; antennce piceee ; thorax 

 albo trivittatus ; pectus cano-tomentosum ; abdomen canes- 

 cens ; pedes picei ; alee subcinereee, vents nigris. 



Fern. Black. Head mostly covered with shining white to- 

 mentum. Antenna piceous, not longer than the head. Thorax 

 with three white stripes. Pectus with hoary tomentum. Abdomen 

 slightly covered with hoary tomentum. Legs piceous. Wings 

 grayish ; veins black ; costal vein ceasing a little in front of the tip 

 of the wing; first branch of the cubital vein undulating, joining 

 the tip of the costal ; third submarginal vein joining the fourth on 

 the border ; subanal joining the anal at some little distance from the 

 border. Halteres black, with testaceous knobs. Length of the 

 body 2J lines ; of the wings \\ lines. 

 a. Para. From Mr. Bates' collection. 



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