3 i6 Professor Williston on the 



SYRPHID^.* 



Mekomacrus. 

 E-ondani, Esam. di var. sp. Ids. Bras., 10, 1848. 



1. Meromacrus pratorum. 



Syrplius pratorum, Fabricius, Sjst. Ent., 765; Enfc. 



S.vst., iv., 286. 

 EristaHs pratorum, Fabricius, Syst. Antl., 236 ; 



Wiedemann, Auss. Zw. Ins., ii., 166. 

 Pteroptila pratoriun, Osten 8acken, Catalogue, 113 ; 

 Williston, Synopsis, 183. 



Twelve specimens. Wiedemann's description applies 

 well, save that it is not stated that the sutural thoracic 

 band is interrupted. The species will be distinguished 

 from M. ruficTus by the separated spots at the base of 

 the abdomen ; from all the other known species by the 

 entirely yellowish red legs. 



Ekistalis. 

 Latreille, Hist. Nat. des Crust, et Ins., xiv., 363, 1804. 



1. EristaHs vimetorum, 



Syrphus vinetorum, Fabricius, Ent. Syst. Suppl., 562. 



EristaHs vinetorum, Fabricius, Syst. Antl., 235; 

 Wiedemann, Auss. Zw. Ins., ii., 163 ; Macquart, 

 Dipt. Exot, ii., 2, 42 ; Williston, Synopsis North 

 Amer. Syrphidse, 171, pi. vii., fig. 8 ; Trans. Amer. 

 Ent. Soc, XV., 280 ; Biologia Centr.-Amer. Dipt., 

 iii., 6S ; F. Lynch, A. Dipt. Argentina, Syi'phidae, 

 116; Giglio-Tos, Dit. Messic, ii., 7. 



EristaHs trifasciatus, Say, J. Acad. Sci. Phil., vi., 

 165 ; Compl. Wr., ii., 359. 



EristaHs uvarum, Walker, List, iii., 623. 



Hah. North, Central and South America, and the 

 West Indies. 



* By S. W. Williston. 



