14 



DIPTERA. 



their tibise and the basal joints of their tarsi, 

 Wings tinged with yellowish ; stigma yellow. 

 Length 9 millim. 



Hab. Costa Eica, Eio Sucio (Bogers). 

 Two specimens. 



and the extreme base of the hind tibiaB, reddish-yellow. 



The following species described by M. Bigot are unknown to me : — 



Melanostoma(%) anthracoides, Bigot, Ann. Soc. Ent. Fr. 1884, p. 82.— Panama. 



(?) annuliferum, Bigot, loc. cit. p. 84. — Mexico. 



(?) quadrinotatum, Bigot, loc. cit. p. 77. — Mexico. 



cyaneocinctum, Bigot, loc. cit. 1885, p. 251. — Mexico. 



As regards M. anthracoides, the yellow scutellum and coloured wings render the 

 location in this genus doubtful ; it is, more likely, an Ocyptamus. M. annuliferum 

 cannot be a Melanostoma. M. quadrinotatum is apparently a true Melanostoma, but 1 

 do not recognize it amongst our specimens; there is a discrepancy of importance 

 between the diagnosis and the description. 



EUPEODES. 



Evpeodes, Osten Sacken, Western Dipt., in Bull. U.S. Geol. & Geogr. Survey, iii. p. 328 (1877). 



1. Eupeodes volucris. 



Eupeodes volucris, Osten Sacken, Western Dipt., in Bull. U.S. Geol. & Geogr. Survey, iii. p. 329 1 ; 



Willist. Synopsis N.-Am. Syrphidse, p. 65, t. 3. figg. 14, 14 a \ 

 Syrphus perpallidus, Bigot, Ann. Soc. Ent. Er. 1884, p. 90 3 . 



Hab. Noeth America 3 , Washington 2 , California 1 2 , Nevada 1 2 , Utah 1 2 , Kansas 2 , 

 Colorado 1 2 , New Mexico 2 , Arizona 2 . — Mexico, Northern Sonora (Morrison), Mexico 

 City (H. H. Smith). 



SYRPHUS. 



Syrphus, Fahricius, Syst. Ent. p. 762 (1775). 

 Scceva, Fahricius, Syst. Antl. p. 248 (1805). 

 Ischyrosyrphus, Bigot, Bull. Soc. Ent. Fr. p. lxviii (1882). 



Syrphus, as now restricted, is, I believe, pre-eminently a European and North- 

 American genus. Many species have been described from South America, but I believe 

 they will be mostly found of heterogeneous forms when they shall have been studied 

 in the light of modern dipterology. I am acquainted with several species which have 

 to be placed in the genus at present, though wanting in the homogeneity that charac- 

 terizes most of those now placed there. I have, however, seen a Syrphus, in the 



